Update 8 p.m.
Main Street in Ellicott City is now open in both directions as the water from the Patapsco River has receded.
Update: 4:30 p.m.
The Patapsco has receded at the Main Street bridge. It's currently about a foot below street-level.
Howard County Police are asking business owners along Main Street to evacuate as the Patapsco River threatens to rise over the Main Street bridge, flooding the area for the second time today.
The rain has flooded the Tiber River, causing the Patapsco to swell as well, according to Lt. Coyle of Howard County Fire and Rescue.
Main Street is closed from the Baltimore County Line to Cacao Lane restaurant.
BGE has been called to cut the power as water threatens electric boxes in basements along the street.
"We're just kind of waiting now to see what Mother Nature's going to do at this point," Coyle said.
The water, he said "could easily rise."
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