Water Savings FAQ

When water is delivered through irrigation systems, some water is lost in the system on the way to customers, through things like seepage or evaporation, this water is called a loss. When irrigation areas are modernised to achieve water savings, the efficiency of the delivery system increases, and less water is lost in delivering the same volume of water to customers. The reduction in losses needed to run the system creates water savings.

Water savings occur when permanent improvements are made to the irrigation system that reduces the water lost in the system on the way to customers, such as seepage and evaporation.

The Water Savings Protocol provides a consistent and transparent method to estimate water savings across Victoria.

The Water Savings Protocol reflects current best practice for the estimation of water savings. It is updated periodically as required to reflect improvements in technology and development in the understanding of irrigation system losses.

Water Savings Protocol updates ensure the associated water savings are estimated in a consistent and transparent manner using the most current scientific information. With this technical update, improving readability has also been prioritised to help ensure consistent use and eliminate ambiguity.

All water savings from major irrigation modernisation projects in Victoria, including the GMW Connections Project, must be estimated and audited in accordance with the Water Savings Protocol.

The Water Savings Protocol contains a technical manual on how to estimate water savings. It also sets out roles and responsibilities and the audit process.

The audit process requires an independent auditor to verify that the water savings estimates have been estimated consistent with the methods described in the Water Savings Protocol. The audit process provides confidence that the water savings are being estimated correctly.

The Victorian Government has appointed two firms, Cardno (Qld) Pty Ltd and Arup Pty Ltd to a panel of independent water saving auditors.

The panel selection was based on an open tender process and chaired by Mr Paul Baxter, a member of the Murray-Darling Basin Authority Independent Audit Group. Mr Baxter is Senior Commissioner of the ACT's Independent Competition and Regulatory Commission. An important requirement of selection to the panel was that firms have had no prior engagement related to the Victorian irrigation modernisation works.

At the end of each irrigation season an independent audit is undertaken of water savings achieved by GMW Connections Project and other modernistation projects as required. The results of these audits are then published on this website.

In accordance with the Water Savings Protocol, the auditors confirm the actual water savings estimates that have been achieved from the GMW Connections Project and other modernisation projects as required at the end of an irrigation season. Long-term average water savings are also estimated for the same years.

The auditor confirms the water savings by:

• Checking that the actual and long-term water savings were estimated consistently with the methods in the Water Savings Protocol for the quantification of water savings
• Checking that the data collection and inputs are as accurate as could reasonably be expected to estimate water savings;
• Conducting spot checks to confirm that the program of modernisation works has been implemented as documented in the water saving estimates;
• Checking that water savings have been estimated based on the nature and the extent of all modernisation works completed up to and including a given irrigation season;
• Providing a corrected estimate of the water savings for any component where the project proponent estimations are found to be non-compliant or deficient; and
• Identifying potential improvements to the data collection, data analysis, assumptions and methods used to estimate the water savings.

Water savings protocol (PDF, 2.4 MB)

The findings from the GMW Connections Project audit for each irrigation season are posted on this website along with a summary of the latest audit. This will continue each year until the end of the GMW Connections Project.

The actual water savings generated in a year depends on how much water is delivered in that year and what modernisation works have been completed.

Long-term annual average water savings are an estimate of the average annual water savings that would have been achieved from the modernisation works over the last 115 years.

The GMW Connections Project water savings targets (Stage 1 of 225,000 megalitres and Stage 2 of 204,000 megalitres) are expressed as a long-term average. Estimating the long-term average water savings demonstrates how the GMW Connections Project is progressing towards this long-term water savings target.