> Water and River Murray > Basin, River Murray, Lakes, and the Coorong > Water for the environment

Water for the Chowilla Floodplain

The specific ecological objectives for environmental watering at the Chowilla Floodplain are to:

maintain river red gum, black box, river cooba, and lignum populations
improve abundance and diversity of grass and herb-land, flood dependent understorey, and aquatic vegetation
create conditions for colonial waterbirds breeding
maintain or improve the diversity, abundance, and distribution of key bird species
maintain or increase the diversity and extent of distribution of native fish species
maintain successful recruitment of small and large bodied native fish
maintain sustainable communities of the eight riparian frog species recorded at Chowilla
improve the distribution and abundance of the nationally listed southern bell frog.

The long-term aim is to improve the condition of the floodplain for plants and wildlife to ensure it is conserved for future generations to enjoy.

How water delivery works

Water for the environment has been delivered to the Chowilla Floodplain Icon Site since 2004. In that time, water has been pumped or gravity fed to 29 wetland sites across the floodplain.

The Chowilla Creek environmental regulator and ancillary regulators are operated to raise water levels in the anabranch creeks to generate widespread managed inundation at relatively low River Murray flows. When operated to its maximum height we can inundate up to 45 percent of the floodplain, depending on River Murray flow.

The infrastructure was constructed under The Living Murray Environmental Works and Measures Program.

Operating the regulator

We plan 'managed' watering events to target a particular height of regulator operation at Chowilla. The regulator can be operated over a range - up to 3.55 metres above the pool level of the anabranch creeks.

The effects of floodplain watering depend on the level of inundation we aim for:

Low level managed inundation	To raise and vary water levels within the channels of anabranches and creeks
Medium level managed inundation	To raise water levels to a height where water flows out into wetlands and starts to spill out onto the broader floodplain
High level managed inundation	Where the regulator is operated to generate broad scale inundation of the floodplain and its wetlands
Pumped delivery	Delivery of water by pumping to individual wetlands, lakes, or small confined areas of floodplain
In conjunction with natural flooding	Water for the environment may be used prior to or following natural flooding to increase the duration and extent of the watering to allow waterbirds and frogs time to complete their breeding

Water for the Chowilla Floodplain — Environmental watering infrastructure enables us to generate broadscale inundation across the floodplain.

Timing

Extensive monitoring of trees, understory vegetation, birds, fish, and surface and groundwater across the Chowilla Floodplain has been happening for several years. Data from monitoring guides the decisions about how, where, and when water for the environment is required.

Water for the environment is delivered in-line with the SA River Murray annual environmental watering plan and priorities (find it here).

Other factors influencing how and when we deliver water for the environment include:

level of flow in the River Murray
availability of environmental water
water quality (salinity and dissolved oxygen levels) in the incoming water.

In some years, water for the environment may be delivered to a lower level or for a shorter period. If the health of the floodplain is declining and there is enough flow in the River Murray, we may plan a large-scale watering event.

Access to the area

When water for the environment is delivered, Chowilla Game Reserve will remain open for the public to enjoy. There will be some restrictions in access to parts of the reserve when the Chowilla regulator is operated at medium and high levels (as occurs with natural floods), as low-lying parts of the floodplain will be covered with water.

When the regulator is in operation, and also when there are significant increases in river flows that result in higher water levels, boat passage through the regulator is not possible. However, boating above and below the structure is unrestricted.
The creeks above the regulator will not be closed to boating or canoeing during an inundation event, however conditions will change and access under bridges may be restricted.
Depending on the scale of operation, some campsites and access tracks may close during the period of operation.
When the regulator is not operating, you can access the floodplain and creeks as usual to enjoy the natural beauty of Chowilla.

During watering events, you can find out information at the Department for Environment and Water Office in Berri and on the Parks website.

Does watering work?

Long-term scientific monitoring tracks the ecological condition of the floodplain in connection with the ecological objectives listed at the top of this page. Monitoring also informs decision-making around how we manage water for the environment delivery.

The monitoring program includes trees and understorey vegetation, fish, frogs, waterbirds, woodland birds, soils, and groundwater.

For details:

Highlights from 2023/2024 ecological monitoring

Plants

Black box woodlands, River Cooba, sedges and other flood-responding vegetation were benefited.

Aquatic flora emerged, with tiny free-floating species present in shallow water.

Frogs

Six of the eight frog species expected for the region were identified in response to wetland inundation, including the Vulnerable Southern bell frog.

Birds

A total of 60,021 wetland birds were counted and identified on the Chowilla floodplain during wetland inundation events in 2023-24.

58 different wetland bird species were recorded using the floodplain including migratory waders, 15 threatened species, and cryptic species such as the shy Baillon’s crake.

There were several sightings of the Endangered white-bellied sea-eagle, including some young birds.

More than 60 species of terrestrial birds were provided a variety of feeding and breeding habitats.

Fish

Native species comprised just over half of the survey catch biomass, with carp gudgeon the most abundant among native species captured.

Werta Wert wetland provided a native fish refuge with a dominant small-bodied native fish assemblage.

Overall common carp abundances were significantly lower compared with the previous year.

When Chowilla gets a drink

Watering the Chowilla Floodplain

How to stay informed

Information about access and watering events is provided through the DEW office in Berri.
Sign-up to receive the weekly River Murray Flow Report via email for information on when water levels will rise, expected water level depths and the expected duration. View previous reports.
Find out how to get involved in environmental water planning or sign up to our occasional newsletter by contacting us at DEW.Chowilla@sa.gov.au
Join a reference group.