Modern pump technology has been central to the $189 million refurbishment of Manton Dam, strengthening Darwin’s water supply system.
Manton Dam was completed in the year of one of Darwin’s darkest days, when Australia was under siege from Japanese bombers during World War II.
Now, the reliable asset that kept water flowing to the Top End in those fraught times, is coming back online, more than 80 years on.
Manton Dam, which has taken a back seat in recent decades as Darwin River Dam has served as the primary water source for the Darwin region, is returning to service.
The $189 million project is funded by the Federal Government through the National Water Grid Fund, in partnership with the Northern Territory Government. Works include delivering a new water treatment plant and bringing Manton Dam back online as a drinking water source for the Darwin region in partnership with government-owned utility, Power and Water Corporation.
Power and Water senior project manager Liam Early tells us more.
“Darwin River Dam was commissioned in the early ‘70s, so it’s a 50-year-old dam, and a succession plan is being put in place for a new facility,” he told Pump Industry.
“We are getting fairly close to maximum capacity from our pump station and main water source at this dam, and it’s time to boost Darwin’s supply from another water source.”
As of late October 2025, the Manton Dam return to service project was well over halfway complete, with a new pump station almost finished along with the refurbishment of an intake tower.
A pipeline from Manton to the new Strauss water treatment plant is also nearing completion, with almost 50 per cent of the Strauss facility constructed.
Once back in service, Manton Dam will provide a further 7300 megalitres (ML) of water per year to the Darwin region, enhancing water security for existing residents and supporting economic growth for the Northern Territory, including the proposed Middle Arm Precinct located in Darwin Harbour.
Middle Arm Precinct is positioned as a globally competitive industrial centre that can support industries such as low-emission liquefied natural gas, renewable energy, carbon capture utilisation and storage, hydrogen, and critical minerals processing.
The project, which will leverage common-user infrastructure, is still in its planning and design stage, with a Strategic Environmental Assessment underway.
“Middle Arm will eventually be home to industries that will require a new water supply and Manton Dam will play an important role in supporting any increased demand in the system beyond normal urban growth,” Early said.
Once back online, Manton Dam will provide a 20 per cent increase in water for the Darwin region.
“When we commission Manton Dam next year, that water will go straight into the Darwin system,” Early said. “This takes the pressure off Darwin River Dam, and provides an important additional supply to the region for our residents and future industry growth.
Power and Water is working with contractor Exact Contracting to construct a new pump station at Manton Dam, which Early said would “provide an efficient and reliable water supply”.
“The last technology was installed in the ‘60s, so the pumps were well and truly past the end of their life,” Early said.
“The old pump room had four pumps. We now have two Sulzer SMD 250-365 B pumps with 200kW motors (one duty, one standby), with each one able to deliver up to 20ML/day to the Strauss water treatment plant, providing a consistent base supply to Darwin.”
Modern tech
The pumps are also being fitted with state-of-the-art technology, with automation enabling operators at the Strauss water treatment plant located 22km away to control water flow remotely.
There are several other advancements occurring too.
“The new Strauss water treatment plant is part of a much larger site that plans to also provide treatment to Darwin’s next planned water source, the Adelaide River off-stream water storage,” Early said.
“This first stage of the Strauss water treatment plant is designed with 20ML per day of treatment capacity. A range of pumps will pump water from the treatment cells through the process plant and into two 2.5ML on-site treated water tanks.”
Valves connected to the intake tower at Manton Dam have been modernised so operators can easily open and close intakes. Exact Contracting has also constructed 22km of new pipeline to support the return to service project.
Early has seen industrial technology evolve rapidly in recent years. In the context of water supply, this is helping operators make quicker decisions to ensure water reaches the right places quicker, saving costs in the process.
“One thing you have to consider is that when you’ve got multiple water sources, you want to extract the best from them,” Early said. “Water doesn’t all pump from the same place, and you need to consider energy costs, water quality and water security objectives.
“So you will want to make decisions dynamically, and through advanced monitoring systems installed across the Manton Dam project, this information is gathered in our supervisory control and data acquisition systems in real time.
“This not only enables us to control water flow from afar but also generates actionable insights that can further benefit our operations.”
Early said the immediate priorities at Manton Dam are to complete the construction of the pump station and pipeline, with commissioning of these facilities to commence by mid-2026.
“We’ll also continue to advance the Strauss water treatment plant, which has been the most complex aspect of the project,” Early said.
“While working with the contractor at Strauss, we’re also optimising the functional design of the facility, so once it’s commissioned, we’ve got a clear operating philosophy in place.”
Power and Water will also be working to integrate Manton Dam’s operation with the Darwin River Dam, which will remain a key asset into the future.
Other undertakings
As Power and Water looks to prolong the life of the Darwin River Dam, the utility is also upgrading its 50-year-old pump station, where construction commenced in late 2024.
“The new pump station there will have more capacity than the current facility, and feature modernised pumps and control systems,” Early said. “That is also planned to come online next year.”
Early said, through smaller upgrades over the years, the existing Darwin River Dam pump station is performing its role, delivering about 80ML per day into the system during the wet season, and up to 160ML during the dry season.
With Manton Dam’s return to service and modern pumping systems in place, Power and Water is thinking long-term when it comes to maintaining Darwin’s water supply system.
Combining Manton Dam and Darwin River Dam not only secures supply for a growing population but positions Power and Water to support future economic development across the Darwin region.
This feature appeared in the Summer 2025/26 edition of Pump Industry.
