Lauren Winstead, 23, of Richmond, and Sarah Erway, 28, of Chesterfield County, haven't been seen since going over the 12-feet-high dam just after 3 p.m. on Memorial Day, Henrico police told the Associated Press.
Officials didn't say what kind of craft they were in, but witnesses saw rafts and paddleboards caught in the current beneath Bosher Dam after the incident.
Rescue crews searched for the women late into Monday night and resumed the search early Tuesday morning.
Officials said the James River is running very high at several spots, but the water would have appeared calm from above the dam. That hid the danger of the churning current at the bottom.
Finn Gardner, who lives near Basher Dam, said someone banged on his window to beg for help after 12 people fell into the river on Monday.
"So, we ran out there, and we were trying to help get people out of the water and make sure that everyone was accounted for," he told WWBT. "... Unfortunately, we couldn't find two of them," Gardner said. "I'm hoping that they're in someone's house somewhere trying to find a way to contact their group. You got to hope for the best."
Officials said anyone who plans to enter the James River should be cautious.
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