Determining catchment scale priorities for riparian protection and rehabilitation.

In Australia, river management decisions are increasingly being made at the catchment scale. There are well established procedures for setting restoration priorities, however catchment managers need objective assessments of catchment condition to help them prioritise restoration works. We describe the application of two catchment-scale assessment techniques, SedNet and the Rapid Appraisal of Riparian Condition (RARC), to determine priorities for protection (fencing) and rehabilitation (replanting) of riparian vegetation in the Murrumbidgee catchment. SedNet is a model that constructs sediment budgets, and the RARC is an assessment of the biodiversity and function of riparian zones. Priorities for bank erosion control were determined by bank erosion hazard, which accounts for stream power, the presence of erodible soil, and channel incision. Priorities for riparian condition were determined using a remotely sensed dataset of existing riparian vegetation cover. The techniques are demonstrated in the Murrumbidgee catchment, where they are being used to assist setting priorities for river restoration. A method for combining the priorities from SedNet and RARC is described, to address objectives of improving water quality and riparian condition.