WATCH: Man trapped on rock in raging waters rescued

NEVADA COUNTY, California (NBC News) — Dramatic video from the California Highway Patrol shows a swimmer being rescued by helicopter after he was stranded on a rock in the middle of turbulent river in northern California.
It happened Aaturday in the Emerald Pools just south of Lake Spaulding in Nevada County.
A swimmer thought he could swim across the rushing river but realized it was too much.
He made his way to a rock in the middle of the rushing water where he sat waiting for help.
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