Millewa Pump Station

Tonkin, with extensive experience in water resource management, was engaged to provide civil, mechanical, electrical, and structural engineering services for the detailed design of a new pump station at Lake Cullulleraine, located in north-western Victoria.

The New South Wales Department of Primary Industries proposed changes to the operations of Lock and Weir 9, in alignment with the Murray-Darling Basin Plan and the Sustainability Diversion Limits project. As a result, a new pump station was required to ensure continued water transfer from the River Murray to Lake Cullulleraine, supporting both irrigation and recreational needs.

Lower Murray Water (LMW) had previously faced issues with the river’s water levels dropping below the pump’s design pool, leading to pump failures. In addition, growing irrigation demand in the region necessitated an upgrade to the existing infrastructure.

The existing pump station had a capacity of 1,480 L/s with one pump, but LMW sought to increase this to 3,500 L/s. To achieve this, three new pumps were installed at the same location, replacing the old system.

Given our extensive experience with pump station projects along the Murray River, Tonkin was well-positioned to undertake this upgrade. Our prior work with LMW, including projects like SMP 1, the Irrigation Mains Replacement Program, and the Sunraysia Modernisation Project 2, demonstrated our expertise in detailed design, construction support, and client liaison.

This previous experience enabled Tonkin to understand the local constraints and deliver practical, stakeholder-focused solutions.

The new Millewa Pump Station officially opened in early 2024.

Our local presence in Mildura enabled our team to work closely with LMW and the construction team, and regularly liaise with various stakeholders.

We frequently accessed the site to ensure the most appropriate design solutions were developed, including our Geotechnical Engineer who conducted various investigations onsite to ensure accurate and detailed reporting. This was also very beneficial where unexpected challenges were realised through the construction phase such as a major river flood where we assisted the contractor in accelerating certain elements of the work to minimise the flood damage to the site.

Tonkin carried out several environmental assessments and prepared detailed reports to ensure that disruption to local flora and fauna was minimised throughout the project. In line with sustainability practices and the guidelines of the Victorian Mallee Irrigation Region, a comprehensive Site Environment Management Plan (SEMP) was also implemented to further reduce the project's environmental footprint.

Tonkin built efficiencies into designs, ultimately saving our clients money through cost-effective capital deployment and optimising maintenance requirements of the facility. 

Although initial concept design was completed by another consultant, Tonkin developed and refined the design. 

In collaboration with LMW and the contractor, Tonkin identified opportunities to refine design elements, ensuring alignment with LMW's intent and expectations while also pursuing efficiencies in both the construction and operation of the new pump station

Our design allowed steel piles to be driven into the riverbank, with suction pipework, fish screens, and supporting steelwork fabricated off-site and on the embankment before being lifted onto the piles. This approach eliminated the need for divers, resulting in significant cost savings and reducing associated OHS risks.