Statistics to help target better environmental water flows
Helping governments and communities ensure the greatest possible ecological benefits are achieved from ‘environmental flows’ (water released specifically to improve environmental condition) through the analysis of data collated from monitoring programs.
With valuable water resources reallocated from irrigated agriculture to ‘environmental flows’ (water released specifically to improve environmental condition), governments and communities are seeking accountability to ensure the greatest possible ecological benefits are achieved from the limited resource.
Ecologist Associate Professor Angus Webb has been leading research to analyse data collated from environmental flow programs, to assess the benefits of these major investments in the environment they offer. He uses statistics to identify patterns in ecological responses to managed flow releases, in Victoria’s Goulburn-Broken Catchment, and as part of the Murray-Darling Basin Plan Environmental Flows Program.
Monitoring programs provide data on a broad range of flow-affected parameters, including water quality, algae, insect life and vegetation. However, Assoc Prof Webb says healthy fish populations remain the most widely relatable criterion for measuring success.
Analyses of Victoria’s Goulburn River program data show an increase in spawning of the iconic Golden Perch and an improvement in population structure. This is based on monitoring data generated from 2008 to 2015.
Assoc Prof Webb says data analysis is now being used to ‘tweak’ the timing and flow volumes based on responses to previous events, to further improve outcomes, in conjunction with expert opinion.
The Victorian research has contributed to the design of coordinated and consistent data collection for Murray-Darling Basin environmental flows as part of the Long-Term Intervention Monitoring Project, which began in 2014. Along with six partner institutions drawn from academia, research institutes, consulting and management, Assoc Prof Webb coordinates data collection and analysis in the Lower Goulburn River as one of seven reference sites across the Murray-Darling Basin. The project is overseen by the Commonwealth Environmental Water Office, and the basin-wide program involves more than 50 project partners.
Assoc Prof Webb says a consistent method for bringing data together allows researchers to infer flow variation at the reference sites, and to predict the effects of future flows.
It also allows us, potentially, to make predictions about flow responses at sites that haven’t been monitored, as part of optimising benefits from flows, he says.