Murray Irrigation
Drainage Review
Project summary
Following the rain events in October and November 2022, where the Murray Irrigation (MIL) footprint received almost 300mm of rain, the company commenced a review into the performance of our drainage system and processes during these unprecedented rainfalls to identify where improvements could exist.
This review was undertaken by an independent Incident Cause Analysis Method (ICAM) investigator, SAFCOM Risk Management, and involved an extensive interview process with customers as well as MIL staff.
Suggestions that arose from this interview process included:
- Investigate the practicality of increasing the capacity of drains
- Reviewing MIL's Maintenance Plan, in particular the company's weeds maintenance program
- Customers who break the rules should be penalised
- Investigate changing the drainage system from a non-regulated system to a regulated system.
The key findings were released in a report completed in June 2023, which provided the company with 45 recommendations that could be adopted to further mitigate the risk to MIL and customers should a flood event of this nature reoccur.
A copy of this report was released to customers on 8 June 2023 and can be accessed via the button below.
The MIL drainage network is designed to drain 50mm of rain within four days after the event. However, due to the unprecedented rain event, the drainage network was inundated and unable to drain that level of water. After undertaking an internal assessment of the review, MIL was able to categorise the 45 individual recommendations into four main items including:
- Engineering assessment of all MIL assets, including all drainage assets in the footprint.
- The development of business cases, based on the drainage review, to seek approval for works where a positive cost/benefit analysis can be identified.
- A full internal document control process review.
- Update to MIL's training plan.
Current Progress
MIL understands the importance of considering which recommendations to implement from the drainage review, and has been working through them since the report was finalised in June 2023. However, these bodies of work need to be prioritised within the organisation based on other high priority works, resources and the costs incurred to complete them. The current progress of these actions are outlined below.
Engineering assessment
As announced in January 2025, Murray Irrigation is undertaking comprehensive asset condition inspection project to collect valuable data that will inform the company’s asset management strategy.
To complete these asset inspections, the company has engaged specialist consultants to survey and collect data, using aerial photogrammetry and in-channel bathymetric survey, across all MIL's civil and earthen assets, including the drainage system.
This extensive survey (Stage 1) was completed in July 2025.
Stage 2 of this project, which involves a digital assessment of the survey data, is now underway and will provide the company with a comprehensive condition assessment of all infrastructure, which may result in future upgrades to the drainage system. This digital assessment is expected to take 12 to 18 months.
Business Case Development for potential works
The issues identified during the review process were run through the company’s risk assessment procedure to determine priority works on the drainage system.
It is important to note that many of these works had previously been identified under the company’s asset management strategy, and had already been scheduled for completion.
The initial risk assessment has prioritised the following items to develop business cases to seek approval for works.
- Wakool flood structures - to investigate potential works that would eliminate flood waters entering the channel system over six sites on the Northern, Mallan and Jimaringle channel systems.
- Inability to read drain levels remotely - to investigate new technology that would allow for the remote reading of drain levels.
- Escapes need to measure height and flow of water - to investigate new technology that would allow for the measurement of height and flow of water through escapes.
- DC 1000 pump site - to investigate the viability of installing a drainage water pump from the DC1000 drain on the Moulamein-Barham Road and its feeder drains to pump water over the structure at times when the Wakool River is backed up and doesn't allow for gravity drainage.
- Hindleys road pump – the refurbishment of the pump station on the Riverina Highway at the Hindleys Road intersection, including the installation of two-way valves and remote monitoring as well as resealing the drainage inlet into the Mulwala Canal. This project is currently under construction as part of the 2025 Winter Works program.
Points 1 and 3 above were assessed through the
Commonwealth funded feasibility study the company undertook during the first half of 2025. In response to shareholder feedback, MIL chose not to progress with these works via government funded avenues. However, further work will be undertaken in the future to undertake these activities as part of the company's normal asset management processes.
Internal document and process reivew
The drainage review identified 23 individual internal document and process review actions for improvement, which can be summarised in the following four categories:
- Improved customer communications during events.
- Increased roster numbers to ensure a minimum staff level at any one time.
- Improved and more time effective drainage application process.
- Internal and external review of responsibility and approval for drainage into waterways, as opposed to MIL drains.
10 of these 23 individual actions have been completed, with the remaining activities underway.
Internal Training
Four internal training initiatives were identified during the drainage review, including upskilling staff in drainage processes, customer service and, importantly, training staff on how to deal with abusive customers.
MIL has since implemented a Zero Tolerance policy which can be found here.
Other identified training activities are being integrated into the company's annual staff training activities.
Business as usual
Outside the recommendations provided by SAFCOM, MIL continues to maintain our infrastructure via the company's annual maintenance strategy.
For further information on this, visit our 'maintaining our infrastructure page' via the button below.
