Now a Scottish Government consultation has been launched on a river basin management plans aimed at improving the physical condition of these waterways.
Paul Wheelhouse, the Environment Minister, said this could deliver many benefits for human health and the environment, from reducing flood risk to habitat protection.
The plan will involve five pilot schemes in river basins from the Dee in the north-east to the Solway in the south-west.
The consultation contains proposals on how agencies can work together to maximise the opportunities available for improvements.
Mr Wheelhouse said: "Water is hugely important to the success of many of our iconic products and industries and makes a valuable contribution to the quality of life in Scotland. That is why we must continue to do all we can to protect our water environment."
He said Scotland's River Basin Management Plans set out key objectives and the Scottish Environment Protection Agency had committed a large amount of resources into meeting these.
The pilot catchments are the River Dee, the South Esk, the River Nith and the River Glazert.