A 14-year-old boy has been rescued in the Australian state of Queensland, after he was left clinging to a tree in raging flood waters.

The emergency worker who pulled the teenager to safety in the Rockhampton suburb of Frenchville was then swept under a nearby bridge but was able to reach safety.

The Australian Bureau of Meteorology said Rockhampton has recorded its wettest January day since 1939, with 161 millimetres (6.33 inches) falling in 24 hours.

The rescued boy walked away from the scene after reaching land and was taken to hospital as a precaution.

Around 20 water rescues were carried out in central Queensland on Thursday night and into Friday morning.

Many of the streets in Rockhampton were left flooded, while strong winds persisted as part of a low pressure system that was once Cyclone Oswald.

More than 70 roads, including major highways, have been cut across the state, since Oswald was downgraded after crossing the Cape York Peninsula's west coast on Tuesday.

Rockhampton resident Justin Parle said he had to take action to stop his property being flooded.

"The house underneath is pretty flooded so we've been digging concrete and everything all morning trying to get the water away," he told local media.