For most Canberrans, interaction with water and sewerage networks starts at the tap and ends at the drain. If water flows from the tap and tastes and looks good, and sewage goes away, we’re happy.
If you consider Canberra’s water and sewerage networks as an iceberg, most people only see the visible tip.
Behind the scenes, dams, bulk supply mains, treatment plants and reservoirs are essential to keep water flowing and our lives going.
Reservoirs of all shapes and sizes are scattered across Canberra. They stock drinking water until it needs to be supplied to customers.
When it comes to ACT reservoirs, it’s hard to ignore the role of quiet giant Mugga Reservoir, one of Canberra’s biggest water reservoirs.
Mugga Reservoir is an older reservoir, and needed a few repairs this year so it could continue to perform its important role.
“Mugga Reservoir is a drinking-water storage reservoir,” explains Icon Water project engineer Andre Verbeek-Martin. “Water flows to it from our treatment plant and gets stored there. As it’s needed by other reservoirs or by people’s properties, it will flow out from the reservoir and provide the water they need.”
Mugga Reservoir’s role can be a little hard to grasp as it does not always distribute water directly to customers.
Its primary role is of a balancing tank. It takes a relatively constant flow of water from Icon Water’s treatment plant and stores extra flow when customers need less water. This additional water is available when demand is high, or when there is maintenance activity at the water treatment plant.
“Every morning, thousands of Canberrans will wake up, flush the toilet and jump in the shower, and that creates huge peak demand over the network,” says Andre.
“When that happens, the water is going to be fed by Mugga to another reservoir like it. This helps to manage the effect of water demand change on our water treatment plant.”
At full capacity, Mugga Reservoir holds more than 45 million litres, or the equivalent of more than 18 Olympic swimming pools. Only the reservoirs in Aranda and Spence – 70 million litres – contain more water.
To protect the water it contains, Mugga Reservoir needs to be covered. Its massive roof has a surface of around 6700 square metres – approximately the size of a football field.
As the roof was reaching its end-of-life in recent times it needed to be replaced. Large cranes were used to remove the previous roof, which was then recycled. The new roof structure, purlins and cladding were then installed.
The sealing joints between concrete slabs of the walls and floor also needed to be resurfaced to maintain the reservoir’s integrity to store water. The old joints’ seals have been restored and covered with almost 3km of ‘bandages’. These will ensure the reservoir is watertight for years to come.
“Mugga was built more than 50 years ago,” says Andre. “This project rejuvenated the reservoir so it will continue to provide clean drinking water to Canberra for another 50 or 100 years.”
The Mugga Reservoir’s new roof is just one of the projects Icon Water is delivering to ensure water quality and security in Canberra. Upgrades to the Googong water treatment plant and O’Connor Reservoir are some of the other projects on the way for Icon Water.