About the area
West Wimmera groundwater management area (GMA) incorporates the area from the west of the Wimmera River to the South Australia border, and north to the Big Desert.
The area is largely dependent on groundwater for urban and agricultural water supply, the main resource being the Tertiary Limestone Aquifer. This aquifer is the primary supply for domestic and stock, irrigation and town supplies across the area.
The West Wimmera Groundwater Management Strategy sets out the rules on how the area is to be managed.
There are 6 management zones within West Wimmera GMA, some of which also have sub-zones. Management rules can differ slightly within each sub-zone.
The area that extends 20 km east from the border forms part of the Designated Area for the purposes of the 1985 Border Groundwaters Agreement between Victoria and South Australia.
Management responsibilities within the Designated Area are shared between Grampians Wimmera Mallee Water and the Government of South Australia.
More information on the GMA can be found on the Grampians Wimmera Mallee Water
Groundwater level trends
Table 1: Groundwater level trends, West Wimmera GMA
Response to water availability
Groundwater restrictions
80% restriction in the Neuarpur subzone 1
Licence holders in the Neuarpur subzone 1 — a trading zone in the West Wimmera GMA — were restricted to 80% of their licence volume in 2024-25, the same as the previous year.
Entitlements and use
Groundwater entitlements have been issued for licensed (non-urban) use and urban supply to Apsley, Edenhope, Goroke, Harrow, Kaniva, Kiata, Lillimur, Miram, Nhill and Serviceton in the West Wimmera GMA. Groundwater is also available for domestic and stock use.
Entitlement volumes
Table 2: Groundwater entitlements at 30 June, West Wimmera GMA
Available water and take
The table below shows the total water available and taken under entitlements, and estimated domestic and stock use in 2024-25. Total water available under entitlements is calculated as the sum of: opening carryover from the prior year (where available), allocation issued during the reporting year, and the net trade in or out of water, across all entitlements. The level of allocation issued is reduced if there are any restrictions in place.
Estimated domestic and stock use is calculated based on an assumed usage per registered bore per year. In this GMA, the assumed usage is 2 ML per bore per year.
More information on groundwater use and availability has been detailed in How we account for
Table 3: Available water and take, West Wimmera GMA
Compliance
Compliance against water entitlements is reported against zones/subzones for this groundwater management unit (GMU) in 2 areas:
- entitlement issued: that the volume of entitlements issued against zones/subzones in the GMU do not exceed relevant permissible consumptive volumes (PCVs) or have not increased without appropriate approvals
- water extracted: that the volumes of water taken under entitlements during the year do not exceed the total water available to licence holders.
Key points on compliance against entitlements in 2024-25
Increase in total entitlement volume
There was an allowed 20 ML increase of entitlement volume for the Ullswater subzone from the previous year.
Entitlement volumes did not exceed PCVs
The volume of entitlements for each West Wimmera GMA zone/subzone did not exceed relevant PCVs.
Total volumes extracted under licences were within the available volumes
The total volumes extracted under licences for each West Wimmera GMA zone/subzone were within the volumes available for the year.
Table 4: PCV vs total entitlement volumes, West Wimmera GMA Zones/Subzones
Management responsibilities
Management of water in the West Wimmera GMA is undertaken by various parties.
| Authority | Management responsibilities |
|---|---|
| Grampians Wimmera Mallee Water |
|
| Government of Victoria / Government of South Australia |
|
