The Times of Gainesville reports that fire crews responded to the call Monday night on the south end of the lake, in the Big Creek Park area near Holiday Marina.
Crews resumed the search early Tuesday.
Hall County sheriff's Deputy Nicole Bailes tells The Atlanta Journal-Constitution that a woman was last seen jumping off a boat around 8:20 p.m. Monday and didn't resurface. Her name wasn't released.
Fire spokesman Scott Cagle said crews didn't have an exact location to search in water that is 80 to 90 feet deep in the area. He said the Department of Natural Resources was using radar in the search.
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