Rivers throughout Otago are to be surveyed so the Otago Regional Council can build up data on how they are changing.
Cross-section surveys are completed on five or six rivers a year on a five-year rotation, council environmental engineering and natural hazards director Gavin Palmer said.
After each survey, the cross-section was compared with the previous one to see if the river had changed.
The information could then be used to manage gravel extraction and waterway capacity.
The council had called for tenders for the work as it could not do it itself, he said.
