Macalister Avon Irrigation Development Project

The aim of the Macalister Avon Irrigation Development Project is to explore the potential to develop irrigated agriculture in the area east of the Avon River in Gippsland. This project is supported by Action 7-2 within the Central and Gippsland Sustainable Water Strategy.

The feasibility study, completed by our specialist consultants in early 2024, builds on feasibility studies previously undertaken through the Southern Victoria Irrigation Development Project and undertook a more detailed assessment of the potential pipeline route options and cost-benefit analyses to identify return on investment.

The Macalister Avon project has now been consolidated with other projects in the Macalister Fresh project, which provides a vision for future irrigated development in the region through to 2050.

Over the past five years Southern Rural Water has undertaken two significant pieces of work to investigate and assess opportunities on the Latrobe and Avon Rivers.

This work was co-funded by the National Water Infrastructure Development Fund and the Victorian Government. These packages of work undertook broad-scale water resource availability and land capability assessments to determine areas where suitable land coincided with potentially available water.

Following this, pre-feasibility work was completed to prepare preliminary concept designs of new water delivery systems, water demand assessments, desktop environmental and cultural heritage assessments, economic and cost-benefit analysis to further prioritise areas.

More recently we furthered this work to include a more detailed assessment of demand for water in the identified area and assess customers willingness to invest and pay.

Previous studies have indicated the Macalister Avon Irrigation Development Project could deliver an estimated $58 million in benefits and an estimated 440 direct, on-farm full-time equivalent jobs, as well as local flow on employment of 495 full-time equivalent jobs.

The project has the potential to relieve irrigation pressure (extraction) on the unregulated Avon River.

Horticulture is expanding in the Boisdale area and currently, the area experiences a season ‘shut down’ in winter between May and August. The Macalister Avon Irrigation Development Project could provide the Boisdale area with a year-round supply that would support expanding high-value vegetable production.

The Macalister Avon Irrigation Development Project will help us to better understand the reality of these potential benefits.

The Macalister Avon Irrigation Development Project area is situated east of the Avon River around Llowalong and along Freestone Creek and covers approximately 6,000 hectares of farming land.

The water resources assessment in the most recent feasibility study found Southern Rural Water channels have adequate spare volume to supply 6,000 megalitres per annum. However, there is limited spare channel capacity to meet peak demands, or most of the irrigation demands during the peak summer demand periods.

The preferred water supply option only uses 50 megalitres per day of the maximum available 80 megalitres per day of spare channel capacity. This has the benefit of allowing continued flexibility of existing channel operation and any future requirements of the Macalister Irrigation Distrcit customers.

To date, we have undertaken crucial technical studies that allow us to better understand the available water resources today and tomorrow under a range of future climate scenarios.

These studies also help inform a functional design for a pipeline network and balancing storage, water savings and losses, channel operation and service, environmental and cultural heritage considerations, project costs and economic analysis.

Through this study we hope to understand the costs more clearly as we move from a concept design of the distribution network and balancing storage to a functional design.

Findings from recent work have indicated that design and construction costs would range from $30 to $36 million, depending on the route option selected.

We will be developing a business case and through the process will determine more accurate cost estimates and will assess different funding models.

An estimated 30 gigalitres of water savings have been created through the phase 1 and 2 Macalister Irrigation District Modernisation program. We propose that a proportion of this water could be used to supply the Macalister Avon Irrigation Project area. We will undertake modelling to determine the availability of these water savings under different climate scenarios.

No decisions will be made about the allocation of these water savings before we speak with our customers. 

The Macalister Avon Irrigation Development project is guided by a set of principles that aims to ensure decision making is sound, equitable and protects existing users – this includes the environment.

If the new supply is implemented, then it is anticipated current surface water use will decline, restoring natural flows to the Avon River. This would increase the amount of refuge habitat for fish during the low flow season and increase survival.

The Macalister Avon Irrigation Development project is guided by a set of principles that aim to ensure decision making is sound, equitable and protects existing users – this includes cultural heritage values of the area. Where possible we will seek to enhance cultural values and access to Country and its resources including water. 

A Cultural Heritage Management Plan is being prepared. We will partner with Gunaikurnai Land and Waters Aboriginal Corporation to complete the field-based cultural heritage and values assessments that will inform the pipeline network design and future works.

Fieldwork is scheduled to take place in the second half of 2024. Previous modernisation projects have uncovered valuable cultural heritage. 

We will investigate the impacts of increased irrigation as part of the technical works packages.

Any future irrigation will need to comply with relevant legislation and the Irrigation Development Guidelines developed by the West Gippsland Catchment Management Authority to ensure best practice irrigation.

The most recent feasibility study found the Macalister Avon Irrigation Project area could be supplied via the Main Northern Channel system. 

The project scope is planned to improve the service to existing Macalister Irrigation District customers on the Main Northern system.

The Macalister Avon Irrigation Development project will be delivered in several phases. The project has now been consolidated with other projects in the Macalister Fresh project, which provides a vision for future irrigated development in the region through to 2050.

Consultation through the Macalister Fresh project will inform the use of water savings from Macalister Irrigation District modernisation and provide a decision-making framework for future projects. 

If the Macalister Avon project is supported through this process, then we will be able to proceed to a business case. This will provide information required by the Victorian Government to consider future funding decisions.

We established a customer and stakeholder reference group in 2022 with members from government agencies and Macalister Irrigation District and Avon River customers to support the delivery of the most recent Macalister Avon Irrigation Development project feasibility study. We are grateful for their time and expertise in providing advice and local knowledge to ensure project outcomes are technically sound.

A new reference group made up of customers and agencies has been convened to advise on the Macalister Fresh project which will provide the pathway for the next phase of the Macalister Avon project. We are preparing a business case that will be completed in 2024 and will include our customers and stakeholders in future conversations about the project.