Groundwater Levels - December 2009
Note: The groundwater section of the Monthly Water Report is updated on a quarterly basis. The next update will be March 2010.
A new approach to determining trends has been adopted in the December 2009 report. This approach recognises changes in season and distinguishes between short and long term trends.
Drought and climate change affect all aquifers, as recharge to groundwater is largely dependent on rainfall. The short and long term trends determined in groundwater management units need to be considered in light of 15 years of reduced rainfall and therefore recharge. Declining trends are likely to be caused from a combination of reduced rainfall infiltration and groundwater extraction.
Groundwater level trends in Water Supply Protection Areas (WSPAs) and Groundwater Management Areas (GMAs) as of December 2009 are summarised below.
- Groundwater levels are categorised as declining in the short term (< 5 years) for 17 of the 25 WSPAs. Groundwater levels for the long term trends (>10 years) are categorised as declining for 13 of the WSPAs.
- In the remaining WSPAs groundwater levels are categorised as stable.
- Management Plan’s either have been prepared or are being prepared in 12 WSPAs. Local Management Rules are now in place in the Mid Loddon WSPA.
- Of the 38 GMAs groundwater levels are categorised as declining in the short term (< 5 years) in 17 areas, stable in 9 areas, and there is insufficient information (through lack of state observation bores) to determine a trend in the remaining 12 areas.
- The next groundwater update will be provided at the end of March 2010.