Groundwater levels in Gippsland
In the upper aquifers
In the middle aquifers all local areas show some level of decline with the exception of the Giffard Groundwater Management Unit. The shallower middle aquifers (Sale and Giffard GMUs) show seasonal fluctuations in contrast to the deeper middle aquifers (Rosedale and Yarram GMUs) which show long-term regional decline but no observable seasonal fluctuation.
The two aquifer formations in the lower aquifers show different groundwater level trends: the Latrobe Group shows a long-term regional decline while the Older Volcanics formation near Moe and Leongatha shows a seasonal pattern similar to the upper aquifers.
What are the groundwater level trends in local areas across the region?
To view the data for any observation bore within the Gippsland region visit our Gippsland region map page. The data is presented as hydrographs. For basic guidance on how to read a hydrograph visit our How is groundwater monitored page.
Below is a summary of the groundwater level trend in a selected bore from each GMU.
Denison GMU: Bore 42069 is in the Macalister Irrigation District. There are no State Observation bores in Denison however groundwater levels are monitored by the Catchment Management Authority for salinity management purposes. Groundwater levels have declined since 1996 which may be due to irrigation modernization however recent data suggests there is no ongoing decline.
Orbost GMU: Bore 115733 is near the Snowy River north west of Orbost. Groundwater levels fluctuate seasonally due to pumping and climate, however the long-term trend is stable.
Tarwin GMU: Bore 94815 is in beach sands at Venus Bay. Groundwater levels fluctuate seasonally due to pumping and climate, however levels have remained stable over 20 years.
Wa De Lock GMU: Bore 110167 is near the Freestone Creek near Briagalong. A seasonal pumping and recovery cycle occurs in this bore, however the long-term trend is stable.
Wy Yung GMU: Bore 80760 is near the Mitchell River on Soldiers Rd. Step rises in groundwater levels indicate a response to floods, however the long-term trend is stable.
Giffard GMU: Bore 145090 is near Woodside. Small seasonal changes in groundwater levels occur due to pumping and climate, however the long-term trend is stable.
Rosedale GMU: Bore 92177 is north of Stratford. A steady regional decline of 5 metres has occurred since 1985. There is no observable impact from rainfall or pumping.
Sale GMU: Bore 86669 is near Stratford. Groundwater levels show a seasonal pumping and recovery pattern. Annual maximum levels in this bore have fallen by 5 metres in step declines since 1996.
Yarram GMU*: Bore 64835 is near Longford. Groundwater levels show a steady regional decline at a rate of 0.5 metres/year over the period of record keeping since the mid 1980’s.There is no observable impact from rainfall or pumping.
Leongatha GMU: Bore 71148 is north-east of Leongatha. Groundwater levels fluctuate seasonally due to pumping and climate, however the long-term trend is stable.
Moe GMU: Bore 107971 is near Moe. Groundwater levels fell during a dry period in the late 1990s and recovered, however they are slowly falling again.
Stratford GMU: Bore 47063 is near Bairnsdale at a distance from the irrigation bores. Data shows a long-term declining trend, however no seasonal influences can be observed indicating that the cause is regional.
Yarram GMU*: Bore 110726 is near Yarram at a distance from the irrigation bores. Data shows a long-term declining trend, however no seasonal influences can be observed indicating that the cause is regional.
* Yarram GMU occurs in both the middle and lower aquifers.
Learn the basics
To find out more about how we monitor groundwater visit our How is groundwater monitored page.