Summary
The 2020 Tamar Estuary Report Card shows an overall improvement in grades across all zones of the kanamaluka/Tamar estuary, compared to the 2018 Report Card.
The smallest improvement was seen in Zone 3 (Swan Point to Rowella), which changed from a B- to a B, both years associated with ‘good ecosystem health’. Zone 1 (Launceston to Legana) is in ‘poor ecosystem health’, an improvement from the ‘fail’ grade in the 2018 Report Card.
Impacts from the extreme weather events shown in the 2018 Report Card, such as low dissolved oxygen concentrations caused by the 2016 flood, are no longer observed in the data used for the 2020 Report Card. Improvements in wastewater treatment plant operations have resulted in reduced effluent nitrogen at the Norwood and Longford plants by 75%, which may have reduced nitrogen concentrations in Zone 1 of the estuary.
Sediment raking activities occurred in the upper estuary until June 2019, with two days of sediment raking and 17 days of prop washing occurring in the Report Card period, down from 39 days of raking in the previous reporting period. A review of the sediment raking program published in 2019 showed raking activity re-suspended sediment and other pollutants in the water column.
Most total pollutants resettled in the upper estuary close to Launceston, while many dissolved pollutants were elevated in the lower estuary for several weeks after raking ceased. The reduced sediment raking program in the 2020 Report Card year has resulted in improved water quality as seen by the improved concentrations in nutrients and metals, particularly aluminium, arsenic and cadmium.
Media release – Roger Jaensch, Minister for Environment and Parks, 20 July 2020
Health of Tamar Estuary continues to improve
The Tasmanian Government is taking action to improve the health of the Tamar Estuary, and today’s Tamar Estuary 2020 Report Card confirms we are delivering on this commitment.
The report monitors the long term health of the Tamar and guides the scientific and evidence-based management of the waterway, with today marking the seventh report card to be released.
The report card shows improvement in water quality across all zones, indicating an overall improvement in the health of the Tamar Estuary, with the greatest improvement seen in the Zone 5 Marine Zone where the grade increased from C+ to A+.
Improving the health of the Tamar Estuary is a key commitment from the State Government, which is why the State and Federal Governments are investing $95 million to initiate the key actions of the Tamar Estuary Management Taskforce’s River Health Action Plan.
The Government has provided the Tamar Estuary and Esk Rivers Program with $185,000 in funding over the last three years and a decision to extend for another 12 months will ensure its important work can continue.
We will continue working with all relevant stakeholders at local, state and federal level to ensure these improvements are maintained in coming years.
The report can be found here: www.nrmnorth.org.au
