About the area
The Hopkins-Corangamite groundwater catchment covers a large area of south-west Victoria.
The catchment contains the Bungaree groundwater management area (GMA), Cardigan GMA, Colongulac GMA, Gellibrand GMA, Gerangamete GMA, Glenormiston GMA, Newlingrook GMA, Paaratte GMA, South West Limestone GMA, Loddon Highlands water supply protection area (WSPA), and Warrion WSPA. The area not covered by these is reported as outside management units.
The South West Limestone GMA extends to the west beyond the Hopkins-Corangamite groundwater catchment. The Loddon Highlands WSPA has a very small section within this catchment and is mostly contained within the Loddon groundwater catchment.
Groundwater resources within the catchment supply licensed entitlements, domestic and stock use, and urban use to Dean, Ballarat, Carlisle, Port Campbell, Timboon, Peterborough, Curdie Vale, Beaufort, Darlington, Mortlake, and Streatham.
Groundwater resources from the Wimmera-Mallee groundwater catchment supply Willaura, although it is located inside the Hopkins-Corangamite groundwater catchment.
More information on water management and accounting is detailed in Water explained.
2023-24 overview
Urban supply
Groundwater supplied to 11 towns in the catchment.
Water use
More water was used for consumptive purposes than the previous year.
Climate
Rainfall
Less rainfall was received in the Hopkins-Corangamite groundwater catchment in 2023-24 than the previous year, ranging from below the long-term average to the lowest on record across the catchment. Rainfall was:
- below average in the east of the catchment around Meredith
- very much below average in a band across the north and east from Willaura to Winchelsea
- the lowest recorded in the reference period (1975 to 2024) for the remaining southern portion of the catchment.
Figure 1 displays the rainfall received in 2023-24 compared to the long-term average (1975-2024).
Figure 1: Rainfall deciles, Hopkins-Corangamite groundwater catchment
Sourced from the Australian Bureau of Meteorology
Groundwater level trends
In the Accounts, groundwater level trends for groundwater management units (GMUs) have been determined by monitoring data from key bores in the State Observation Bore Network. Trend determinations are made quarterly by comparing each reading to a previous reading in the same season 5 years prior; for example, a summer record is compared to the summer record from 5 years earlier to account for seasonality. These trends are shown in Table 1 below.
Groundwater resources are being actively managed. For more detail on management responses, go to on the Southern Rural Water website.
In 2023-24, groundwater level trends toward the end of the year were rising in 5 GMUs, stable in 2 GMUs, and declining in 2 GMUs. A trend for Newlingrook could not be determined towards the end of the year due to data availability, however it was rising in the prior quarter ending March 2024.
There are insufficient state observation bores in the Glenormiston GMA to adequately define the groundwater resource or changes to the resource over time.
Table 1: Groundwater level trends, Hopkins-Corangamite
Response to water availability
Groundwater restrictions
There were no restrictions on licensed groundwater use in 2023-24, the same as previous year.
Entitlements and use
Groundwater licence and use volumes in the Hopkins-Corangamite groundwater catchment are shown below. Domestic and stock use does not require a licence, so in the Groundwater availability and take table (Table 3), these rows only report water taken.
The licensed volume used under entitlements must not exceed the volume made available to individual licensed entitlement holders. We report on compliance in the GMU local reports and in the Statewide groundwater summary.
Water used
Use in the Hopkins-Corangamite groundwater catchment was 26,216 ML, more than the 21,265 ML used in the previous year.
Entitlement volumes
Rights to water in the Hopkins-Corangamite groundwater catchment are shown below.
Table 2: Groundwater entitlements at 30 June, Hopkins-Corangamite groundwater catchment
Available water and take
The table below shows the total water available and taken under entitlements, and estimated domestic and stock use in 2023-24. 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 catchment, the assumed usage is 1.5 ML usage per bore per year.
More information on groundwater use and availability has been detailed in How we account for
In 2023-24, 26,216 ML of water was extracted for consumptive purposes, which was more than the 21,265 ML extracted in the previous year. Of this volume, 23,074 ML was for non-urban (irrigation) use, 1,173 ML was for urban use, and 1,969 ML was estimated to be for domestic and stock use.
Table 3: Groundwater availability and take, Hopkins-Corangamite groundwater catchment
Management responsibilities
Management of water in the Hopkins-Corangamite groundwater catchment is undertaken by Southern Rural Water.
| Authority | Management responsibilities |
|---|---|
| Southern Rural Water |
|
