Implementing environmental flows is an important step in restoring riverine ecosystems impacted by flow regulation. The rapidly changing climate now presents a challenge for environmental flow determinations as ecosystems undergo potentially rapid and irreversible change. ‘Climate ready’ flow targets represent an aspirational goal of establishing restoration targets today that are considered feasible under the future climate regime.
To assess whether ecological objectives from flow assessments can be considered ‘climate’ ready we assessed 422 environmental flow objectives in water management plans from Victoria, southern NSW and the Murray River in South Australia.
Our survey showed most environmental flow targets are set with reference to historical flow regimes, and most don’t consider future climate or hydrological scenarios in determining whether past ecological states can be maintained under future conditions of water availability, thermal regimes etc. Very few objectives include proactive management strategies to sustain ecosystems under altered climatic conditions. None of the documents included hydrologic modelling of future flow. It is reasonable to conclude that any climate adaptations included in existing objectives are untested with no evidence to support their ‘achievability’.
This research shows the environmental water industry in south east Australia is currently underprepared for a future climate and ensuing hydrologic and ecological change. This lack of forward planning creates a risk that environmental water will be ineffective in achieving desired goals,and potentially maladaptive in a changing climate. There is an urgent need to establish appropriate frameworks and methods for incorporating climate change into environmental flows objective setting and scenario assessments.