Schemes to use the Tees Barrage to generate electricity in environmentally friendly ways are being investigated.
About 30 to 40 tonnes of water a second flows through
The bridge was designed to maintain a constant water level as well as a crossing for vehicles.
Large quantities of natural debris like branches are caught in the barrage when they are washed down the river.
A feasibility study is being carried out into the possibility of burning the debris as well as using water and wind power to generate electricity.
River manager Alan Slater said: "We are looking at renewable energy supplies. What we have got here is hundreds of tonnes of willow that comes on every spate.
"So working alongside Renew Tees Valley we are looking at whether or not we can utilise this to generate electricity."
He said most of the debris was natural and with some local power stations turning to willow burning, they were looking at how it could be turned to fuel.
He said other resources at the barrage were wind power, with about 30 to 40 tonnes a second flowing through, and the possibility of harnessing wind power with windmills.
He said: "But the debris is a major problem to us. The River Tees is 60 miles long, most of it is tree-lined, so this is a continuous resource that just flows down to us.
"It is just how we process it and how we get it to the power stations."