Georges Riverkeeper recently completed fieldwork to inform River Health grading, despite a few hindrances.
Monitoring of the estuary occurred from December 2019 through to March 2020, travelling from the mouth of the river up to Liverpool Weir to monitor chlorophyll a (indicative of algal productivity) and turbidity (i.e. cloudiness of the water) through the warmer months of the year.
Monitoring the freshwater sites upstream of Liverpool Weir occurred in the months of November 2019 and April 2020.
November monitoring was impacted by catastrophic fire warnings. Heeding bushfire warnings meant that it was not possible to access remote tributaries in the Dharawal National Park. The ongoing drought also resulted in some sites having no water to monitor. However, most freshwater sites were successfully monitored in November.
The April monitoring involved revisiting sites assessed in November to measure water quality and collect waterbugs. Most recently, COVID-19 has disrupted everything, including monitoring of freshwater sites. To comply with social distancing rules, it was not possible to involve interns or volunteers, as we usually do, in scheduled monitoring in April. Instead, Georges Riverkeeper staff assisted with the monitoring: having only two people in the field and travelling in separate cars allowed completion of the fieldwork whilst adhering to social distancing. With recent rain, there were no longer any dry sites and some of the sites had higher flows than observed during previous visits over the past five years.
We now have data for 17 estuary sites and 34 freshwater sites. This data will be used to grade ecological conditions along the Georges River and be presented in a report describing the state of the river to be released towards the end of 2020.
Dr. David Reid from Georges Riverkeeper explains that the conditions or health of waterways can be assessed by measuring turbidity, oxygenation, pH levels, electrical conductivity, and temperature.