WHITTIER (CBSLA.com)  —    Three teens learned a very valuable lesson in where and when to skateboard Sunday.

Don’t skateboard near a wash and don’t skateboard in a storm drain during a heavy rain. It’s dangerous, to say the least.

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As KCAL 9’s Brittney Hopper reports, one of the teens got swept away. The other two found themselves clinging to a fence for dear life.

Very scary moments for the teens who told her that had no idea that much rain was going to fall.

“It was scary. Extremely scary,” said 16-year-old Eric Mendez of Whittier.

Mendez was with two friends, all skateboarding, when the rain suddenly intensified.

“At first the water was rushing really fast like at my knee and we tried getting out but then it kept coming up and at one point it was up to my neck,” said Mendez.

He told Hopper than he and another friend were able to hold onto a chain link fence while the rushing water swept another teen a mile away.

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“He got swept away and at first I started holding onto my friend’s leg and my friend was like just hold on,” Mendez says.

The teen who got swept away was able to get out of the raging water on his own through a manhole cover.

He ran and got help and 911 was called.

At first, firefighters were looking in the area for the other teens where the teen had been swept away and considered two teens missing. But they were still holding onto a fence a mile up the wash.

Mendez’s mother rushed over as soon as she heard what was happening.

“It’s just unbelievable — that someone can come out alive. He said it was about three, maybe four feet of water and the actual gate closed on them so they couldn’t get out,” his mother said.

Firefighters say people should stay out of any washes or storm drains. Especially when it’s supposed to rain. The teens say they know the outcome could have been a lot worse. One of the teens was sent to a nearby hospital for evaluation.

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All three are expected to be okay.