About the area
The South West Limestone Groundwater Management Area (GMA) covers a shelly and sandy limestone aquifer extending into the Hopkins-Corangamite, Portland and Glenelg groundwater catchments from Gellibrand Lower to the south-western border of Victoria. The South West Limestone GMA partially overlies the Newlingrook GMA, Paaratte GMA and Portland GMA, fully overlies the Condah WSPA, partially underlies the Colongulac GMA, and fully underlies the Glenormiston GMA.
The water authority responsible for managing groundwater in the South West Limestone GMA is Southern Rural Water.
The South West Limestone GMA Local Management Plan applies to groundwater resources in the south west Victorian upper mid-Tertiary limestone aquifer.
More information on groundwater management can be found on the Southern Rural website.
Groundwater level trends
Table 1: Groundwater level trends, South West Limestone GMA
Groundwater restrictions
There were no restrictions on licensed use in the South West Limestone GMA in 2022-23.
Entitlements and use
Groundwater entitlements have been issued for licensed (non-urban) use and urban supply to Warrnambool, Allansford and Koroit. Groundwater is also available for domestic and stock use.
Entitlement volumes
Table 2: Groundwater entitlements at 30 June, South West Limestone GMA
Available water and use
The table below shows the total water available and used under entitlements, and estimated domestic and stock use in 2022-23. Total water available under entitlements is the sum of opening carryover, allocation issued and the net trade in or out of water.
Estimated domestic and stock use is calculated based on an assumed usage per registered bore per year. In this GMA, 1.5 ML usage per bore per year is assumed.
More information on groundwater use and availability has been detailed in How we account for .
Table 3: Groundwater availability and use, South West Limestone GMA
Compliance
Compliance against water entitlements is reported for this groundwater management unit (GMU) in 2 areas:
- entitlement issued: that the volume of entitlements issued in the GMU does not exceed relevant permissible consumptive volumes (PCVs) or has not increased without appropriate approvals
- water extracted: that the volume of water taken under entitlements during the year does not exceed the total water available to licence holders.
Key points on compliance against entitlements
The South West Limestone GMA PCV has not been gazetted. The entitlements and use relate to the area defined in the South West Limestone Groundwater Management Area Plan No. LEGL./15-199. The South West Limestone GMA includes the area of the former Nullawarre WSPA, Yangery WSPA, Hawkesdale GMA and Heywood GMA and the areas outside the former GMUs but included within the South West Limestone GMA area. The PCVs for the four GMUs have not been revoked and still apply. PCV volumes are Nullawarre 22,741 ML, Yangery 14,352 ML, Hawkesdale 16,161 ML and Heywood 8,500 ML.
Total volume extracted under licences was within the available volume
The total volume extracted under licences (20,564 ML) was within the volume available for the year (104,853 ML).
Table 4: PCV vs total entitlement volumes, South West Limestone GMA
Management responsibilities
Management of water in the South West Limestone GMA is undertaken by Southern Rural Water.
| Authority | Management responsibilities |
|---|---|
| Southern Rural Water |
|
