Abstract

Environmental infrastructure and practices designed to restore and protect aquatic systems are
now mainstream. Yet many of these projects are failing to produce the biophysical outcomes that
they are designed for because of poor maintenance. The success of restoration projects is just as
much a consequence of how they are maintained, as it is how the project was initially designed
and implemented. Successful maintenance relies on understanding the ecological and biological
recovery trajectories of aquatic systems. Some interventions will require ongoing maintenance
indefinitely, whereas others will reach a self‐sustaining point where maintenance is no longer
required. Different management arrangements are required to ensure the maintenance of different
types of project. Those projects that involve high costs should be managed using more robust
arrangements, such as legal regulation, compared to those projects that involve lower costs. This
paper describes the maintenance required for common river restoration projects and outlines a
classification of projects based on maintenance and recovery trajectories. It then considers the
types of management arrangements required to ensure maintenance. Finally, these points are
illustrated with 3 case studies of typical restoration actions (riparian stock exclusion, fish passage,
and restoring large wood loads). Projects that require ongoing maintenance, particularly those
that involve high costs, such as environmental flows, require strong management arrangements
to ensure successful outcomes. Voluntary instruments are more appropriate for self‐sustaining
interventions. Regardless of the chosen management arrangements, monitoring and independent
assessment are essential for successful maintenance.