Chalk Groundwater Levels

Central Region

*The long term average (LTA) has been calculated statistically, using the long term data record for this hydrograph. The respective drought zones are used as operational triggers and have been derived using the LTA.

Rainfall in our Central region was above average in October at 183% of the Long Term Average (LTA). Over the last three months (August to October), our Central region has received above average rainfall (144% of the LTA) and effective precipitation (197% of the LTA). As a result, soil moisture deficit (SMD) has dipped below average and continues to decline with rainfall as groundwater levels begin seasonal recovery. During this period rainfall contribution to groundwater recharge is more critical.

Groundwater levels remain above average and have started to increase in the final week of October due to the above average rainfall and below average SMD recorded. However, there has been a net reduction through the month. Groundwater levels are likely to remain above the LTA over the Winter and spring period if we receive above 80% of the LTA rainfall. Well below average rainfall (60% of the LTA) may cause groundwater levels to reach the LTA trend in Spring.

Please refer to our Drought Plan for further information about droughts and how we manage them.