Water rescues in Victoria have shot up in the new year, sparking a fresh warning for those misbehaving.

The state’s water police have been called to more than 100 incidents in the first week of 2025, up from 17 during the same period in 2024 and 36 in 2023.

Many of the callouts related to dangerous jet-ski behaviour including speeding, travelling too close to other swimmers and in some cases even colliding with other vessels, police said.

One rescue on Saturday afternoon involved a jet-ski and boat colliding on Safety Beach on the Mornington Peninsula.

A 14-year-old boy who was a passenger on the jet-ski was flown to hospital after suffering serious upper body injuries.

The male rider and a second passenger, aged 43 and 14, also had to be rescued from the water. They were taken by road to hospital.

Two boat passengers came away with minor injuries.

Police seized both the jet-ski and boat as part of their investigation, which continues.

That same afternoon in Rye, a jet-ski carrying three teenage boys nosedived into a wave, throwing all three overboard.

The teens were not hurt but officers had to tow the jet-ski as its hull had broken apart.

Water Police Squad Inspector James Dalton said hot weather was not an excuse to do the wrong thing while enjoying Victoria’s waterways.

“Already we’ve seen multiple serious collisions on the water,” he said.

“These young people are lucky to be alive, but instead of enjoying the summer they’re now recovering in hospital with serious injuries.

“People need to remember that a split-second decision can have lifelong consequences.”

The warning comes after Life Saving Victoria made 145 rescues on Saturday, Victoria State Control Centre spokeswoman Reegan Key said.

“That’s a really high number and, obviously, there are lots of people on holiday at this time of year,” Key said.

“We’re asking people to be a bit more aware and careful as they head to the beach, rivers and lakes.”

Police are planning a heavy presence across Port Phillip Bay, including inner Melbourne beaches and Hastings, the Mornington Peninsula and Surf Coast, as well as Paynesville, for the coming weekend.

Officers will breath test drivers, check marine licences and scan vessels for safety equipment such as lifejackets.

-AAP