Sinkhole causes chaos at nearby school, businesses in Sydney CBD

A sinkhole has opened up on a busy street in Sydney CBD, forcing a nearby school to close and leaving businesses without water.

A burst water pipe created the hole at the intersection of College Street and Prince Albert Road near St Mary's Cathedral today.

Students at St Mary's Cathedral College, which adjoins the church, were sent home for the day.

READ MORE: Man falls two metres down flooded drain as torrential rain lashes Sydney

Sydney Water has been forced to cut off water supply to up to 10 nearby businesses as it works to fix the pipe.

"Sydney Water crews are on site excavating and have isolated the main with a rezone in place so that repairs can commence," a spokesperson said.

"Prince Albert Road is currently closed with diversions in place in order for this critical work to be carried out safely.

"Sydney Water thanks the community for its patience and apologises for the inconvenience."

A Coles truck became stuck in the hole earlier this morning and had to be towed out.

The tyres were damaged, but the driver was able to safely leave once he was helped out of the truck.

Shark warnings

Heavy rain has prompted a shark warning to beachgoers and swimmers today due to the increased potential for shark attacks in the wake of the heavy rain.

"Heavy rain can change beach and waterway conditions quickly," NSW SharkSmart said in a post on Instagram.

"Freshwater and nutrient-rich run‑off can reduce visibility, affecting water quality and attract baitfish – sometimes increasing shark activity."

People are urged to avoid swimming in murky or dirty waters, take extra care within 1km of river mouths and harbours, and be cautious around baitfish, diving birds, and dolphins.

There was a rash of shark attacks after a recent series of storms along the NSW coast, one of which resulted in a young boy's death after he was mauled at Vaucluse.

Experts at the time warned storm activity provided cover for bull sharks and lured them closer to shore and even upriver.​ ​

Sydney recovers from flash flooding

It came as heavy rain that totalled 100mm in some parts and flash flooding hit the Sydney region overnight.

Homes were evacuated as the rain inundated streets in Fairfield East and more than 490 calls were made to the SES.

Out of those, 42 led to swiftwater rescues.

Cars were also flooded in shopping centre carparks while roads were cut throughout the metropolitan area.

The rain has eased throughout this morning, with the Bureau of Meteorology cancelling a severe warning for Greater Sydney.

But flood warnings remain in place for much of outback NSW, Queensland, South Australia, and the Northern Territory.

A near-stationary tropical low system hanging over Central Australia continues to pour rain into all four states, with the heavy downpour slowly moving south.

READ MORE: Queenslanders warned to brace for possible 'cyclone sandwich'

Adelaide is next in line for a soaking, with more than 100mm forecast to fall on the city in the coming hours.

Some events in the city have already been cancelled, with flash flooding expected across the metropolitan area.

Rain also continues to bucket down in dust-dry outback Queensland, with the tiny town of Birdsville, 10km from the South Australian border, copping an extremely rare drenching.

Weatherzone reported that in the 24 hours to 9am yesterday, the town received 93.2mm, more than half of its annual average of 161.4mm.

It was also Queensland's second-highest 24-hour rainfall total behind Fall Creek in the decidedly more tropical Cape York Peninsula.

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