The Victorian Constraints Measures Program (CMP) looks at ways to allow rivers to connect to their floodplains more often to make best use of the available water for the environment, while managing or mitigating effects on local communities and industries.
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General program information
Many of Victoria's river systems have been modified as the state has prospered and population grown, to provide water important for towns, industry, and food production.
Instead of water flowing naturally through the landscape, water is now captured in dams and weirs, with releases of water from dams into rivers controlled by river operators for the ultimate delivery of water to end users via pipes and man-made channels. River operating rules are also in place to protect landholders downstream of dams and weirs from unexpected inundation.
Modern irrigation infrastructure has resulted in some low-lying floodplains have become increasingly disconnected from their rivers. By relaxing or removing constraints environmental water can be used to re-establish elements of the natural flow regimes to put water when and where it is needed, and where it cannot currently be delivered.
These periodic higher flows play a key role in vegetation condition, and provide habitat, food, and the conditions to breed for native animals like fish, birds, frogs, and turtles.
These flows will improve environmental outcomes on the floodplain as well as in the river channel.
The Victorian CMP aims to enhance the delivery of already available environmental water and introduce a more natural river flow in the Goulburn and Murray Rivers. It will examine relaxing constraints in 3 key areas:
- Goulburn River: from Lake Eildon to the confluence with the Murray River (note: this project is focused on in-channel work only)
- Murray River: from Lake Hume to Yarrawonga Weir
- Murray River: from Yarrawonga Weir to the confluence of the Wakool River.
DEECA is working closely with technical specialists, a Consultative Committee, and relevant agencies to undertake the feasibility study.
The scope of the work currently funded is referred to as Stage 1A. This involves appointing a Consultative Committee, undertaking preliminary technical investigations, providing a forum for the exchange and testing of views, and developing a feasibility study. No further funding is committed beyond Stage 1A.
The Victorian Minister for Water will review the study and decide if the program should proceed to subsequent stages.
The Commonwealth Government is funding this feasibility study through the Water for the Environment Special Account (WESA).
In this instance, a constraint is a technical term for anything that reduces the ability to deliver water for the environment.
Constraints can include physical restrictions such as low-lying bridges, crossings, or private land.
Constraints can also include operational aspects such as river rules or operating practices.
This program aims to enhance natural river flows generally up to minor flood levels only.
Before river regulation, overbank flows were common and delivered a range of benefits including:
- improving water quality and supplies, by
- flushing out the salt along riverbanks and floodplains
- helping recharge groundwater supplies
- improving soil quality and reducing erosion, by
- moving carbon and nutrients between rivers and floodplains
- stabilising riverbanks through better plant growth, thus reducing erosion into the river
- supporting native species, by
- triggering plants to seed or germinate – for example, river red gums need flooding for their seeds to germinate
- supporting habitat and breeding of aquatic bugs and insects (the primary source of the river food chain)
- providing the cues and breeding habitat for frogs, such as the threatened growling grass frog, which requires the seasonal inundation of wetlands for breeding in the drier Murray regions
- stimulating animals like native fish to feed and breed – for example, golden perch need high river flows to spawn, and floodplains make great nursery habitats to rear young fish, providing increased connectivity to allow plants and animals to move throughout river systems and colonise new areas.
- Relaxing constraints will also provide cultural and recreational benefits including tourism activities along and, on our rivers, such as fishing and bird watching.
Constraints are a key part of implementing the health of our rivers via the Murray-Darling Basin Plan. Changing the way dams and rivers are managed can help Basin States (South Australia, New South Wales, and Victoria) achieve better environmental outcomes with available water.
Previous business cases have been prepared to investigate options to address constraints on the Goulburn River. The original business case was based on limited information and data. It made assumptions about the potential impacts and is considered pre-feasibility at best.
Victoria and NSW commissioned a review of the modelling, finding that existing modelling was not fit-for-purpose for a project like constraints relaxation.
Community members also raised concerns that Victoria has listened to in developing this current program.
We are now addressing those gaps and community concerns through this feasibility study so that we can determine if the program will progress and can have meaningful conversations with landholders in the future.
The initial project proposals used technical information that was available at the time but was not fit-for-purpose for a project like this. In 2019, the Victorian and NSW Ministers for Water commissioned an independent review of existing modelling.
The feasibility study is being done to action some of those recommendations and to incorporate new and updated fit-for-purpose information (aerial photography, new models, data, river surveys and Geographic Information System tools) and enhanced modelling capabilities. This is to reduce the uncertainties around flow rates and provide better information to landholders should the project proceed to later stages.
Improving the health of floodplains and diversity of plants and animals is good for local communities through cultural and recreational benefits, tourism, as well as support for the local economy throughout any stages where works may be implemented.
Enhancing river flows may result in additional inundation of low-lying floodplain adjacent to the rivers. Generally, this is not where there are buildings. However, this inundation may further impact existing landholder assets such as pumps, culverts, and access tracks. Access to some parts of properties may be limited when the river is operating at higher levels, generally up to minor flood levels.
Stage 1A is producing inundation modelling under changed river operations that will allow an initial assessment to be made about further impacts on landholders along the river. This modelling will be an integral part of any future consultation process with private landholders as it will show what parts of a property may be inundated at different flows from time to time, and what assets and land aspects may be impacted.
If the program progresses to the next stage, these specific impacts will be discussed with landholders as part of one-on-one engagement to refine the impacts further and discuss mitigation options. These mitigations may also provide increased flood resilience against higher flows under natural conditions.
Though water for the environment can mean any water in a river or wetland that benefits the environment, when we talk about 'water for the environment' (or 'environmental water') we are referring to water that's set aside in storages such as reservoirs and dams. This water is used to support particular ecological processes and enhance the health of rivers, floodplains and wetlands.
We are doing a lot of work to understand what a more natural watering regime looks like within our rivers. We are working out which species of plants and animals to target, how much water these species need, what time of year the water is needed, and how long the water needs to stay on the floodplain. These decisions will be informed by environmental studies and surveys, as well as the development of environmental water plans.
Victoria’s Catchment Management Authorities play a key role in working with the community and supporting their environmental water needs.
Instead of flowing naturally (high flows in winter and low flows in the hotter months of summer), rivers now run higher in summer to meet consumptive (including farming) and urban use, and lower in winter when water is captured in storage.
These changes have interrupted many of the natural river and wetland processes needed by native plants and animals to survive, feed and breed.
Water for the environment is released into some of these rivers and wetlands to improve their health and protect environmental values.
Managers of water for the environment generally focus on returning some of the small and medium-sized river flows important in the life cycles of native plants and animals. By relaxing constraints, areas of the floodplain that receive water from overbank flow could be enhanced, reconnecting floodplains to the river.
During Stage 1A the program will assess environmental benefits and impact, including changes to vegetation, connecting fish to temporary floodplain habitats, creation and access to different food resources (quality and quantity), waterbird responses and food webs.
The assessment will be informed by existing information and studies, as well as reporting and updated modelling.
A panel of experts will also review the modelling outcomes and investigations to provide further insights into the environmental benefits and impacts that may result from changed river operations.
No, the program does not seek to cause erosion.
River operators must meet the demands of agriculture, urban water and the environment when delivering water. As such, the river will function within operating rules at a level to meet all these demands and impacts.
Flows being investigated by the CMP include higher overbank flows on the back of naturally high-water levels following rainfall to deliver water to the low-lying floodplain.
Enabling overbank flows will improve the bank condition by dissipating the water energy across the floodplain.
It will also provide the conditions for seed dispersal and riparian vegetation growth, which is expected to improve bank stability.
Yes. Medium and high climate change scenarios have been incorporated in the modelling.
It is important that climate change implications are investigated to assess what environmental benefits may be achieved in the future under these changing conditions and whether there is sufficient water to meet environmental objectives.
It also reduces the risk of investing in assets, also known as stranded assets.
Under a drier climate future, the floodplain is less likely to be reconnected. This helps provide critical flows to protect ecological processes.
Traditional Owners have an enduring connection to Country and an essential role in water resource planning and management.
Stage 1A involves working with Traditional Owners to identify and articulate the cultural, environmental, and social benefits and risks that may arise from changes associated with the program.
If the program is approved, it will be subject to Regulatory Approvals which will incorporate Cultural Heritage Assessments and reporting requirements.
The feasibility study will assess a range of options to relax constraints. The environmental, social and economic benefits, and impacts on landowners and assets of these options will be evaluated and compared with continuing current operating arrangements.
Based on the technical analysis and the Consultative Committee’s insights, the feasibility study will provide advice to the government about the social, cultural, environmental, and economic benefits, impacts and costs of the options considered.
The Consultative Committee has been established to ensure local insights are considered, and to provide advice about the benefits and impacts of options presented in the feasibility study as well as key aspects that should be considered if the program is to progress.
Any future stages will include engagement with the broader community and all potentially affected landholders.
The feasibility study will be provided to the Victorian Government in Q3 2023. The government will then decide whether to proceed to the next stage.
The Victorian Government will consider the findings of the feasibility study, to help decide whether to seek Commonwealth funding for the next stage (Stage 1B).
The primary purpose of undertaking the constraints program is to seek environmental benefits from increased river flows. The program is not being undertaken to enable more inter-valley trade.
Operating and trade rules are in place to ensure trade is enabled where there are no unacceptable third-party or environmental impacts.
Victoria is working with NSW on their Reconnecting River Country Program (the NSW Constraints Measures Program) to ensure a consistent approach across both states, and that the interests of Victorian communities are protected.
We are sharing data and information across states, which supports Victoria in the preparation of its own feasibility study.
The Victorian Government, after evaluating the findings of the feasibility study, will decide whether the program has merit to progress to the next stage.
Stage 2 (Implementation phase) cannot occur without the consent of Victorian landowners, alignment with New South Wales and appropriate funding from the Commonwealth government.
Yes. Funding for the feasibility study has been provided by the Australian Government. The CMP team is working closely with the MDBA who is undertaking the Murray River modelling for this study.
The program is focused only on changing how we deliver environmental water to the lowest parts of the floodplains.
Most impacts are related to the inundation of farmland generally up to minor flood levels where there are generally no buildings. This means that assets such as pumps and pump sheds, culverts and access tracks may be impacted, or higher water levels may restrict access to some parts of properties.
The program is looking at what measures will also be required to mitigate impacts on landholders.
Modelling forms the basis of the CMP. As part of the feasibility study, technical data and information will be updated to further inform hydrologic and hydraulic modelling to provide information as to what land can be watered, to what depth, how frequently and for how long.
It will also provide information around the extent and depth of inundation across an individual property.
If the program proceeds, this modelling will be subject to ground-truthing with stakeholders and be a key factor in further engagement with individual landholders on potential impacts.
If the program proceeds to Stage 1B, the project will commence one-on-one engagement with all potentially impacted landowners.
It is important to note that land will not be inundated without prior consent from landholders and there will be no compulsory acquisition of land or easements for the purposes of this program.
Any compensation considerations will be communicated directly with landowners as the program progresses.
All current releases from dams are managed according to established operating guidelines and planning.
Under any changes, the release of water would continue to be managed according to an agreed plan.
In Stage 1A, aspects that need to be considered with river operations are being investigated.
If the program is to proceed, environmental water deliveries would be made through an adaptive and trial-based approach, starting with smaller flows, to ensure any risks in operations are adequately assessed and mitigated.
The Consultative Committee is chaired by the Hon. Patrick McNamara, with members comprising Registered Aboriginal Parties, local landowners, irrigators, community members, river operators, Council representation, Catchment Management Authorities, land managers, agencies, and others.
DEECA engaged with agencies to identify community members who had experience and knowledge across water-based issues.
Stage 1A's focus is working with the Consultative Committee to investigate whether the program is feasible to move onto the next stage where further engagement, including with individual landowners, would occur.
As part of Stage 1A, a community consultation and stakeholder engagement plan will be developed in conjunction with the Consultative Committee.
This plan will guide a program of extensive, further engagement if the program proceeds to subsequent stages.
DERVS and Catchment Management Authorities have been working directly with Traditional Owners in northern Victoria to create forums for discussion about the impacts of higher flows on the landscape.
As part of Stage 1A, we are working with Traditional Owner groups to discuss technical results and to hold meaningful conversations about the cultural benefits and risks of different river flows. The Traditional Owner groups will guide engagement.
The Consultative Committee also includes members from Registered Aboriginal Parties.
During Stage 1A, consultation is being undertaken with the Consultative Committee and focus group sessions with targeted stakeholders.
If the program proceeds to Stage 1B, comprehensive in-person community consultation will be carried out with individual impacted landowners, the wider community and relevant agencies and stakeholders.
Currently, the Consultative Committee will provide their insights and advice during the development of what engagement in Stage 1B may look like.
Community feedback will be considered at all stages of program development and co-design.
In Stage 1A, the Consultative Committee comprises of community members from across the 3 key river reaches being investigated.
If the program is deemed feasible to move into the next stage, significant community engagement will be undertaken in subsequent stages to inform the program planning and delivery.
Page last updated: 06/11/23