by Linda Mumma

STANISLAUS COUNTY (CBS13) — The Stanislaus County Sheriff’s Office is urging people to be safe on the water following a jet ski collision at the Modesto Reservoir over the weekend.

The crash happened just before 5 p.m. Saturday while jetskier Tim Campbell was on the water with his wife and son.

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“I saw them going up and down the lake,” Campbell said. “You could tell they were definitely too young to be riding by themselves without an adult with him.”

About two hours after he left the reservoir, he learned by watching the news that the girls were involved in a crash.

“It’s crazy because we had just left there,” he added.

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Deputies said the 14 and 15-year-old girls were riding on a jet ski at the reservoir near Waterford when they collided with a boat.

One of the girls was taken to UC Davis Medical Center by helicopter with serious injuries. The other was taken by ambulance to the hospital.

Juan Moreno (credit: Stanislaus County Sheriff’s Department)

Deputies arrested the driver of the boat as part of a DUI investigation.

“I think all parties involved they should be blamed for because the kids were too young. The guy was drinking,” said jetskier Mark Fowler.

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Fowler said the incident hits close to home.

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“I’ve got my daughter here and she just turned 13 and she’s pushing six feet tall,” he said.

He’s got another daughter just a few years younger. While he said both daughters are taller than other girls their age, he won’t let them ride his two Seadoos until they reach 16 years old and are properly licensed.

“I tell them they’re still my babies. Obey the rules or you’re not going to ride. That’s all there is to it. Because these jet skis are no joke. They’re very fast and if they don’t know how to stop them they’re going to run into something and you can’t hear anybody on the water because they’re loud,” he said.

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California law requires you to be 16 years of age or older and in possession of a California Boating Card to legally operate a vessel or personal watercraft with a motor of 15 horsepower or more.

“And that’s why we come during the week because it gets crazy here on the weekend. There’s too many people and too many people are drinking,” he added.

The sheriff department’s Major Accident Investigation Team is now looking into the crash. In the meantime, deputies on the scene arrested 43-year-old Juan Moreno. He now faces a charge of boating under the influence, causing bodily injury.

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The other occupants of the boat did not appear to have any injuries.