About the area
The Kiewa River originates from the Bogong High Plains and flows northwards across approximately 100 km in northern Victoria. It eventually merges with the Mitta Mitta River, to join the Murray River.
Precipitation within the basin primarily takes the form of rain, with snowfall occurring above 1,400 m during winter. Annual rainfall averages range from below 900 mm in the northern areas to over 1800 mm at Mount Bogong in the southern headwaters.
Water resources in the Kiewa basin serve various purposes, including power generation, agriculture, and meeting urban needs.
More information on water management and accounting is detailed in Water explained.
2022-23 overview
Available water
Catchment inflow was higher than the previous year.
Licensed diversion restrictions
There were more 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 2022-23:
- more rainfall was received and catchment inflow was higher
- storages finished the year at higher levels
- there were more restrictions on licensed diversions from unregulated streams
- more water was diverted from the basin for consumptive uses.
Climate
Rainfall
In 2022-23, rainfall across the entire Kiewa basin was very much above the long-term average. This was higher than the previous year when rainfall was similar in the north of the basin, but average in the south.
Figure 1 displays the rainfall received in 2022-23 compared to the long-term average (1975-2023).
Figure 1: Rainfall deciles, Kiewa basin
Sourced from the Australian Bureau of Meteorology
River basin water balance
This section describes the known and estimated inflows, outflows and change of storage volumes in the basin.
The volume of water flowing out of the Kiewa River into the Murray basin represented 94% of the Kiewa basins total inflows.
Water balance table
The table below shows the total volumes of water available and supplied from water resources in the Kiewa basin in 2022-23.
Table 1: Water balance, Kiewa basin
Major on-stream storages
Major - greater than 1,000 ML - on-stream storages in the Kiewa basin are included in the water balance. Volumes in off-stream storages are presented for additional information about the resource condition.
Storage levels
Storage levels were 83% in June 2023.
Higher than the previous year
In June 2022, storage levels were 41% full.
Table 2: Storage levels, Kiewa basin
Inflows
Catchment inflow
Catchment inflow represents the volume of water flowing into the waterways of a basin. It is calculated as the total outflows and change in storage minus the known inflows.
Large rainfall events across much of the state in October 2022 resulted in high flows, which impacted the ability of gauges to provide accurate streamflow estimates for the Kiewa basin. This impacted the estimates of catchment inflows, end of basin outflows and losses in this basin. Alternative methods have been required, which have a lower confidence than the method typically used. However, these methods are considered fit for this purpose of basin-scale water accounting.
An explanation of the methods applied can be found in the method tab of Figure 3.
Above average inflow of 1,225,905 ML was received (181% of the long-term average of 676,700 ML), more than the previous year (121% of the long-term average).
Above average inflow received
Catchment inflow was 181% of the long-term average of 676,700 ML.
More water received than the previous year
Catchment inflow was higher than the previous year (121% 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 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 East Gippsland Water and North East Water.
Outflows
Diversions
In 2022-23, 10,555 ML of water was diverted for consumptive uses: town, domestic and stock, irrigation and commercial supply. This was more than the 9,033 ML diverted in the previous year.
Small catchment dams
Water harvested, used and lost by small catchment dams (farm dams) is included in the water balance.
Table 3: Small catchment dams, Kiewa basin
Entitlements and compliance
Entitlements provide the basis for how water is shared in the basin.
Consumptive diversions under bulk entitlements are assessed against the Murray-Darling Basin annual cap target for the Murray-Kiewa-Ovens Valley. Details of this assessment are published annually in the MDBAs cap register and annual water take report.
Since 2019-20, the consumptive diversions are also assessed against the annual permitted takes under the Murray-Darling Basin Plan Sustainable Diversion Limit (SDL) compliance reporting which are annually published in the MDBAs SDL accounts register of take and the Inspector-General of Water Compliances SDL compliance statement.
Entitlement volumes
Rights to water in the Kiewa basin are shown in Table 4.
Entitlement volumes represent a maximum volume of water 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 can vary. The rules for allocating water under an entitlement differ between entitlements and systems. This affects the ability and likelihood of water being taken in a particular year.
Table 4: Annual entitlement volumes at 30 June, Kiewa 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 2022-23. The volume includes carryover from the previous year, seasonal allocations and net trade into the basin.
Water taken under entitlements
There was 7,544 ML taken under entitlements in 2022-23, more than the previous year (6,386 ML).
Restrictions on licensed diversions from unregulated streams
- Diversions from Bright Creek were banned from March-June 2023.
- All other streams were unrestricted during the year.
- There were no restrictions in place during the previous year.
Available water and take table
This table shows the volume of available water and the volume taken under entitlements in 2022-23.
More information on available water and take has been detailed in How we account for surface
In 2022-23, more water was taken under entitlements than the previous year.
Table 5: Available water and take under entitlements, Kiewa basin
Compliance
Compliance against water entitlements is reported for this basin in 3 areas:
- entitlement issued: that the volume of entitlements issued in a basin does not exceed formal caps, and has not increased without appropriate approvals
- water taken: that 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
- bulk entitlement provisions: that holders of entitlements do not breach any provisions that are documented in their bulk entitlement orders.
Total entitlement volume
There was no net increase in the total entitlement volume from the previous year.
Total volume diverted
The total volume diverted under entitlements (7,544 ML) was within the volume available for the year (20,368 ML).
Individual bulk entitlements
No individual bulk entitlement holder took more than the annual volume made available to them.
Exceptions to compliance
Individual bulk entitlement holders complied with all provisions in their entitlements.
Water for the environment
Environmental watering sites
There are no environmental entitlements in the Kiewa basin, so no active environmental watering occurs.
However, important sites and environmental values in the Kiewa basin that depend on water for the environment include:
- threatened remnant vegetation and Murray cod in the reaches of the West Kiewa River and lower Kiewa River
- nationally significant Alpine wetlands, known as the Alpine sphagnum bogs and associated fens.
Water from the Kiewa basin also flows into the Murray basin, helping to maintain environmental assets in that basin.
Environmental water reserve
In 2022-23, water for the environment in the Kiewa basin comprised:
- water set aside for the environment:
- through flow-sharing arrangements
- through the operation of passing flow conditions on consumptive bulk entitlements held by North East Water and AGL Hydro Ltd
- through the operation of passing flow conditions on licensed diversions
- all other water in the basin not allocated for consumptive uses: this water also provides social, recreational and cultural benefits.
Management responsibilities
Management of water in the Kiewa basin is undertaken by various parties
| Authority | Management responsibilities |
|---|---|
| Goulburn-Murray Water |
|
| North East Water |
|
| AGL Hydro |
|
| North East Catchment Management Authority |
|
| Water supply system | 2021-22 (ML) | 2022-23 (ML) |
|---|---|---|
| Mount Beauty system | 365 | 371 |
| Yackandandah | 151 | 150 |
