About the area
- The Portland Coast basin is in south-western Victoria. Major rivers in the basin include the Moyne, Eumeralla, Fitzroy and Surrey rivers.
- The basin receives 600-900 mm annual rainfall on average.
- Land around the basin is primarily used for grazing and broad acre cropping.
More information on water management and accounting is detailed in Water explained.
2021-22 overview
Available water
Catchment inflow was higher than the previous year.
Licensed diversion restrictions
There were fewer restrictions on licensed diversions than the previous year.
Water use
More water was diverted for consumptive purposes than the previous year.
When compared to the previous year, in 2021-22:
- slightly less rainfall was received but catchment inflow was higher
- there were fewer restrictions on licensed diversions from unregulated streams
- more water was diverted from the basin for consumptive uses.
Climate
Rainfall
In 2021-22, rainfall in the Portland Coast basin was average across the entire basin, slightly lower than the previous year.
River basin water balance
In 2021-22, 1,911 ML of water was diverted for consumptive uses: town, domestic and stock, irrigation and commercial supply. This was more than the 1,565 ML diverted in the previous year.
Water balance table
The table below shows the total volumes of water available and supplied from water resources in the Portland Coast basin in 2021-22.
Table 1: Water balance, Portland Coast basin
Catchment inflow
Catchment inflow represents the volume of water flowing into the waterways of a basin. It is calculated to be the difference between the total outflows and the known inflows.
Below average inflow received
Catchment inflow was 71% of the long-term average of 462,200 ML.
More than the previous year
This is higher than the previous year (53% of the long-term average).
Wastewater treatment plants
Water treated at wastewater treatment plants can be used to supplement water available in the basin. Water discharged to waterways from treatment plants is included as an inflow to the water balance.
Information on treatment plants is now reported in the Water Supply local reports for the water corporation responsible for managing the plant.
In this basin, wastewater treatment plants are managed by Wannon .
Small catchment dams
Water harvested, used and lost by small catchment dams (farm dams) is included in the water balance.
Table 2: Small catchment dams, Portland Coast basin
Entitlements and compliance
Entitlements provide the basis for how water is shared in the basin.
Entitlement volumes
Rights to water in the Portland Coast basin are shown in table 3 below.
Entitlement volumes represent a maximum volume that can be taken in a one-year period. The volume available in a particular year is dependent on the rules for allocating water set out in the entitlement and the seasonal conditions in that year, which varies. The rules for allocating water under an entitlement can differ between entitlements and systems. This affects the ability and likelihood of water being taken in a particular year.
Table 3: Annual entitlement volumes at 30 June, Portland Coast basin
Available water and take under entitlements
Total water available under entitlements represents the volume of water that was available to be taken by entitlement holders in 2021–22. The volume includes seasonal allocations and net trade into the basin.
Water taken
There was 140 ML taken under entitlements in 2021-22, less than the year before (107 ML).
Restrictions on licensed diversions from unregulated rivers
There were bans in place on the Fitzroy River between December 2021 and May 2022, and on the Moyne River between January and February 2022, reaching a peak of two restricted streams in January 2022; this is one fewer than in the previous year.
Available water and take table
This table shows the volume of available water and the volume taken under entitlements in 2021–22.
More information on available water and take has been detailed in the How do we account for page in the “How do we account for surface water” section.
In 2021-22, more water was available and taken under entitlements than the previous year.
Table 4: Available water and take, Portland Coast basin
Compliance table
Compliance against water entitlements is reported for this basin in two areas:
- entitlement issued: the volume of entitlements issued in a basin does not exceed formal caps, and has not increased without appropriate approvals
- water taken: the volume of water taken during the year does not exceed the volume considered to be available for consumptive and/or in-stream use during that year.
Total entitlement volume
There was an allowed increase in the total entitlement volume from the previous year. See note below.
Total volume diverted
The total volume diverted (140 ML) was within the volume available for the year (4,000 ML).
Note to increase in total entitlement volume:
- A new 2,500 ML take and use licence was issued in the system; this was previously unallocated water. The volume was within the cap set in the 2011 Western Region Sustainable Water Strategy.
Water for the environment
Environmental watering sites
There are no environmental entitlements in the Portland Coast basin, so no active environmental watering occurs.
However, important sites in the Portland Coast basin that depend on water for the environment include:
- Lake Condah and the Budj Bim National Heritage Landscape — a site inscribed on the UNESCO World Heritage List — which is a volcanic plain that encompasses the area from Budj Bim to the sea and which supports manna gum woodlands and many rare and threatened aquatic fauna including the Yarra pygmy perch.
- the Fitzroy River – Darlots Creek system, where Darlots Creek flows south from Condah to the Fitzroy River at Tyrendarra and into the Southern Ocean via the Fitzroy River estuary. The area contains several threatened species.
- other important rivers in the basin include the Moyne and Surrey rivers and the Eumeralla / Shaw River system.
Environmental water reserve
In 2021-22, water for the environment in the Portland Coast basin comprised:
- water set aside for the environment through the operation of passing flow conditions on licensed diversions, particularly for Condah Drain, Darlots Creek and the Fitzroy, Moyne and Surrey rivers
- all other water in the basin not allocated for consumptive use: this water also provides social, recreational and cultural benefits.
Management responsibilities
Management of water in the Portland Coast basin is undertaken by various parties.
| Authority | Management responsibilities |
|---|---|
| Southern Rural Water |
|
| Wannon Water |
|
| Glenelg Hopkins Catchment Management Authority |
|
