Mount Cole Pipeline Refurbishment with GWM Water and Interflow

We proudly partnered with GWM Water and Interflow to complete a refurbishment of the Mount Cole Pipeline in Western Victoria.

GWM Water is a country water authority supplying a huge territory in Western Victoria. They provide essential services to rural communities by supplying drinking and non-urban water to thousands of users in remote regions.

Located 24 kilometres east of Ararat—near Victoria’s Grampians mountain range—the Mount Cole Pipeline has supplied water for Ararat and surrounding areas since 1930. The pipeline draws its water from the Mount Cole Reservoir located in the middle of the state forest.

Having been in commission for many years, the pipeline has shown signs of wear, with more than 300m of gravity fall over many kilometres of pipe in extremely challenging topography.

GWM Water engaged Interflow to reline and replace many sections of the older pipeline. By engaging in a refurbishing project, the team would increase the pipe’s flow capacity. In turn, this ensures the 300m gravity fall pipeline can accommodate higher flows while reducing the number of pipe failures downstream.

An extremely reliable hydraulic valve solution designed for harsh, remote operating conditions

Our team was engaged to provide a hydraulic valve solution that controls flow and keeps the hydraulic gradient line at an extremely specific grade.

The Bermad 730EN Sigma valve was selected along with a number of Fox-RFP air release valves as part of the solution. These robust products were strategically chosen to safeguard a high level of performance over time and control the aging infrastructure for many years to come.

A number of new replacement air release valves were fitted to ensure the losses are minimised. This approach maximises the flows along the pipeline while reducing any possibility of the air valves generating water hammer.

Reliable performance in a volatile landscape

The extreme topography of the environment created substantial design constraints for the refurbishment. For example, with the pipeline located in the middle of a dense and sprawling national park—over 760m above sea level—it’s impractical to expect frequent access to the valves. As a result, the supplied valves have to be extremely robust, and designed and configured for long-term performance.

The control valve and air release valves used in the solution are both fully WSAA appraised. Additionally, all valves are fully certified to AS5081 and AS4956-2017, providing security and peace of mind for GWM Water.

In light of the remote nature of the installation, the Bermad 730EN Sigma pressure sustaining valve was specially plumbed in order to enable full online filter servicing. This incorporates a dual LC filter, stagnation tubes and high-pressure stainless-steel balanced sustaining two-way control pilots.

Commissioning the valves—and providing a thorough onsite training program to ensure staff are familiar and comfortable with all valves used in the solution—proved a challenge, given the remote location of the pipeline.

Despite the unforgiving location, it was an extremely rewarding experience to train staff in such a rugged and resplendent natural setting: with seven-foot grey kangaroos looking on and wedge-tailed eagles soaring in the skies above.

To learn more about the specific products used in the Mount Cole pipeline refurbishment, please view the detail pages of:

• The Bermad 730 EN Sigma pressure sustaining valve
• The Fox 3F-RFP full-bore single chamber triple function combination air valve, with a build-in anti-water hammer non-slam surge prevention system.

Or for details on similar designs, please view more of our projects and case studies.