A mass power shutdown across Melbourne’s CBD triggered by a burst water main has caused peak-hour chaos in the heart of the city.

About 10,000 customers in the city’s south-east were impacted and dozens of traffic lights in the area went dark after the water flooded a carpark on Little Collins Street, a Citipower spokesperson confirmed.

The water entered a substation in the basement, resulting in the power being cut in the CBD for safety reasons.

Power outage caused by burst water main Melbourne CBDThe mass power outage caused by a burst water main at a carpark on Little Collins Street. (3aw/Jacqui Felgate)

Footage shared by 3AW’s Jacqui Felgate shows the CBD carpark inundated with water.

The site provides power to around 10,000 people in the south-eastern area of Melbourne’s CBD.

CitiPower was forced to shut off the grid to assess the damage.

“We have been able to restore power to more than 4000 customers by redirecting power supply from other parts of the network,” a spokesperson said.

About 5700 customers were without power as of 5.30pm.

By 7pm, a little under 5000 customers were still offline around the city.

Up to 40 sets of traffic lights across the city centre, East Melbourne and South Yarra were left without power, according to VicTraffic.

“When traffic lights aren’t working, you must follow the same rules at an intersection that has a stop or give way sign or line,” VicTraffic said in a post on X.

Drivers have been warned to stay alert in the impacted suburbs.

Some Metro train lines were delayed by the power shut-off.

“Our crews are on site and working to remove the water so they can safely access the zone substation and assess any damage,” the spokesperson added.

“We will keep customers updated by SMS and on our website on restoration times.”

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