Skip to main content
Go to search page

Highlights in this update

  • Soil moisture deficiency persists despite increased rainfall.
  • Strong flows in the Darling (Baaka) River continue to flow into Menindee Lakes.
  • Water quality threats fall through winter.
  • Spotlight – wet weather and strong flows bolster the Murray system.
Root zone moisture levels for the Murray-Darling Basin, July 2022

Drought

Long-term rainfall deficiencies continue to affect areas of the
Murray-Darling Basin, however conditions have improved in recent seasons and overall storage levels are increasing across the Basin.

Increased average rainfall has contributed to improved streamflow in many catchments, which is aiding supply to downstream areas of the Basin. However, because rainfall is largely concentrated in upstream catchments, low soil moisture in downstream regions is an ongoing trend.

As shown in the map to the left, root-zone soil moisture is below average in many areas of the southern Basin. This is particularly evident in the Mallee region of Victoria and the Riverina region of New South Wales. Localised rainfall will be required to improve conditions in these areas.

Rainfall totals for the Murray-Darling Basin - July 2022

Rainfall

For July, most of the Murray–Darling Basin received average to below average rainfall, trending to lowest on record in the New South Wales Riverina.

Further south, Victorian and South Australian catchments received little significant rainfall, which is reflected in the storage levels in many Victorian dams. Highest rainfall in southern catchments was recorded around the alpine regions in the south-eastern fringe of the Basin.

Conversely, average to above average rainfall was recorded in most of the northern Basin, correlating with good streamflow conditions.
Flows in the Darling (Baaka) River peaked at above 20,000 megalitres per day as water from upstream catchments makes its way south. This water added to storage levels at Menindee Lakes, despite very much below average rainfall in the lower Darling region.

Water storage levels across the Basin as at 3 August 2022

Water storages and streamflow

Overall storage levels in the Basin dropped slightly through July, ending the month at 92%, a 1% fall from the previous month.

Storages in the northern Basin recorded the largest decrease (5%) as reduced inflows allowed many storages to return to, or below, full supply level. Several storages remain above capacity, most notably Lake Burrendong at 111%, more than 100 GL over full supply level.

The southern Basin saw a slight increase in total storage, up 1% on the previous month. Dams in the north central and Mallee regions of Victoria remain comparatively low to other southern areas. Lake Eppalock and Cairn Curran Reservoir are 49% and 58%, respectively.

Upper Murray storages remain close to full. Hume Dam storage reduced slightly to 92% capacity due to airspace management releases in preparation for expected heavy rainfall. Dartmouth Dam level increased by 1% to 96% of capacity.

Storage at Menindee Lakes continues to increase, up 4% to 114% of capacity. WaterNSW is expecting up to 1000 GL of inflows to reach the lakes by the end of October.

Lake Mulwala continues to refill following a recent drawdown to manage the invasive waterweed Egeria densa, with the aim of returning to regular operational level by mid-August.

Climate outlook

The Bureau of Meteorology is forecasting a wetter than average season for the eastern two-thirds of Australia, including the Murray–Darling Basin.

This is mostly due to a negative Indian Ocean Dipole and the expected recurrence of a La Niña later in 2022. This will coincide with lower than average temperatures for eastern Australia.

High streamflows are likely during August and October in eastern Basin catchments.

Summary of threats to water quality in the Basin - August 2022

Water quality

Water quality issues continue to be less of a concern through winter. Nevertheless, the MDBA and state authorities monitor water quality across the Basin year-round. For more information on water quality, and a map of threats, see the water quality page of our website. To report a water quality issue see the water quality contacts page of our website.

Summary of key water quality issues

  • Hypoxic blackwater: It has been a number of years since large flooding events last occurred in the Murray, Murrumbidgee and Edward–Wakool systems, with an anticipated high load of organic matter and carbon on the floodplains. Although storages and flows remain high and there are continuing La Niña conditions, cooler weather will reduce the risk of hypoxic blackwater events.
  • Low dissolved oxygen: With cooler weather the risk of low dissolved oxygen conditions has reduced across the Basin.
  • Blue-green algae: There is currently a low risk of blue-green algae, however conditions have the potential to change rapidly. For the latest information on blue-green algae alerts, contact the relevant state government contacts via the Getting information about current algal blooms page of our website.

Spotlight: wet weather and high flows signal good conditions for the Murray

Image: Water flowing into Menindee Lakes, which has filled to 114% of capacity following consistent inflows from the Darling (Baaka) River over the past 12 to 18 months.


Full water storages coupled with a 50% chance of another La Niña in 2022–23 are driving management strategies in the River Murray System for the year ahead.

Heading into the irrigation season, southern Basin storages are at an unusually high level for this time of year, and it's likely that wet conditions and high flows will persist for at least the next few months.

Hume Dam has been in and out of flood operations for the past 12 months, and Menindee Lakes is currently at 114% of capacity, providing water security for the upcoming irrigation season.

It's also notable that substantial amounts of water for the environment will be delivered through the system this year, including to the Barmah–Millewa Forest, unless natural flows exceed environmental targets.

The MDBA will continue to monitor conditions and adjust river operation strategies as the season unfolds, publishing an update to advise of any changes.