Officials said 150 households were evacuated after rains threatened the integrity of a damn near Lynchburg, Virginia, overnight.

On Thursday, the city of Lynchburg warned its population of 80,000 that "imminent failure" of the College Lake Dam was possible. But during an afternoon news conference Friday, Tim Mitchell, the city's director of water resources, said engineers determined that the dam was "stable."

"We're still concerned about its overall stability going into tonight and tomorrow morning," he told reporters.

Continued rains, however, meant that Lynchburg was not out of the woods. Officials said residents ordered to evacuate should not return to their homes until the rains had fully stopped.

If the dam fails, water levels could reach 17 feet in seven minutes in parts of the city, according to the National Weather Service.

A flash flood watch was in effect until 11 a.m. ET. Water was already spilling over the dam early Friday, threatening about 124 houses in the city of 80,000, according to the Associated Press.

Earlier in the evening Thursday, up to 6 inches of rain fell within a matter of hours, the National Weather Service said, swelling College Lake beyond capacity.

Videos posted on social media showed raging waters in Lynchburg. Emergency personnel were rescuing residents from flooded homes via inflated boats to area shelters.

To alleviate strain on the dam, water from College Lake was being released in a controlled manner.

WATCH: Video from Joni Organ shows raging waters at the College Lake Dam in Lynchburg, Virginia, that officials say is as risk of failing Thursday night. The video was shot around 8:15 p.m. ET, before the water began pouring over the dam. pic.twitter.com/xOHPedRlz3 — NBC News (@NBCNews) August 3, 2018

Lynchburg is about 50 miles east of Roanoke. The area has been pounded for days with rain, and the NWS warned early Friday that there was the possibility of more showers and thunderstorms through Friday night, with up to 3 more inches of precipitation.

"This system is a slow mover. There's not much going on as far as getting relief," "Today" show meteorologist Al Roker said Friday.

The strong storms were part of severe weather along the East Coast, where 36 million people were under a flash flood warning or watch from Georgia up to New England.