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 GMUs is reported as outside management units.
- The South West Limestone GMA extends into the Portland and Glenelg groundwater catchments. The Loddon Highlands WSPA straddles this catchment and the Loddon groundwater catchment.
- Groundwater resources 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.
2021-22 overview
Urban supply
Groundwater supplied 10 towns in the catchment.
Water use
More water was used for consumptive purposes than the previous year.
Climate
Rainfall
Rainfall in the Hopkins-Corangamite groundwater catchment was average in most of the catchment, lower than the previous year. Rainfall was above average in a small area north of Beaufort, south near Forrest, and a small area in the east from Meredith to Bannockburn.
Groundwater level trends
In the accounts, groundwater level trends for groundwater management units (GMUs) have been determined based on 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. That is, a summer record is compared to the summer record from 5 years before to account for seasonality.
Groundwater resources are being actively managed. For more detail on the management responses go to the groundwater on the Southern Rural Water website.
In 2021-22, groundwater level trends in the Hopkins-Corangamite groundwater catchment were mostly consistent with the previous year.
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
Entitlements and use
Groundwater licence and use volumes in the Hopkins-Corangamite groundwater catchment are shown below. Some groundwater licences incorporate domestic and stock use, and in these cases the use is reported in the licensed volume.
The licenced volume used under entitlements must not exceed the volume made available to individual licensed entitlement holders. We report on compliance in the GMU local report and the Statewide groundwater .
Water used
Use in the Hopkins-Corangamite groundwater catchment was 28,284 ML, more than 24,235 ML 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 use
The table below shows the total water available and used under entitlements, and estimated domestic and stock use in 2021-22. 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 1.5 ML usage per bore per year is assumed.
More information on groundwater use and availability has been detailed in the How do we account for section.
In 2021-22, 28,284 ML of water was extracted for consumptive purposes, which was more than the 24,235 ML extracted in the previous year. Of this volume, 25,370 ML was for non-urban (irrigation) use, 779 ML was for urban use, and 2,135 ML was estimated to be for domestic and stock use.
There were no restrictions on use in the Hopkins-Corangamite groundwater catchment in 2021-22.
Table 3: Groundwater availability and use, 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 |
|
