A major power outage across Melbourne’s CBD caused widespread disruption during peak hour after a burst water main flooded critical infrastructure in the city centre.
According to CitiPower, around 10,000 customers in Melbourne’s south-eastern CBD area were affected after water inundated a car park on Little Collins Street. The flooding reached a basement substation, forcing authorities to cut power for safety reasons.
The affected substation supplies electricity to approximately 10,000 residents and businesses in the south-eastern section of the CBD. As of 5:30 pm, around 5,700 customers were still without electricity.
A large power failure has caused up to 40 sets of traffic lights to be out across the CBD, East Melbourne and South Yarra. When traffic lights aren’t working, you must follow the same rules at an intersection which has a stop or give way sign or line. #victraffic pic.twitter.com/AZ77Pw19yj
— VicTraffic (@VicTraffic) May 25, 2026
CitiPower said crews had successfully restored power to more than 4,000 customers by rerouting supply through other parts of the network.
The outage also disrupted transport and traffic across the city. VicTraffic reported that up to 40 traffic lights in Melbourne’s city centre, East Melbourne and South Yarra had lost power, prompting warnings for motorists to remain cautious in affected areas.
Several Metro train services also experienced delays due to the shutdown.
CitiPower said crews remain on-site, working to remove floodwater and safely access the substation to assess any damage.
“We will continue providing customers with updates through SMS and our website regarding restoration times,” the company said.