By Bill Shields

BOSTON (CBS) – Two kayakers are safe and sound, but learned a hard lesson about Boston Harbor in the spring. “I think the temperature of the water was 40 degrees,” said Joe Matthews of the Boston Police Harbor Unit. “But everyone thinks because it was a nice day, everyone’s out having a good time enjoying the harbor, having a good day and when you go in the water it’s dangerous.”

The two kayakers left Carson Beach in Saturday afternoon, but the heavy southwest wind pushed them toward Thompson Island, then, when they tried to turn around, their kayak filled with water.

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Boston Harbor (WBZ-TV)

They made it to a navigation buoy, and held on. “They were in hypothermia when we got to them,” said officer Dave Perez. “They were trembling and couldn’t hardly speak.”

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And if not for a Good Samaritan with a pair of binoculars, the outcome may have been tragic. He was at the JFK Library, and spotted the pair in the water, and called the Coast Guard, who put out an emergency distress call and the Boston Police heard it, and responded, rescuing the two kayakers.

Boston Police Harbor Patrol (WBZ-TV)

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“They were lucky to get to the buoy,” Matthews said. “Because they were in the water about 30 minutes. Much longer, and they wouldn’t have made it.”