The National Weather Service on Wednesday issued a flood warning for the Roanoke and New River valleys, as local governments and businesses, including Carilion Roanoke Memorial Hospital, prepared for high water along the Roanoke River.
By 9 p.m. Wednesday, 5.94 inches of rain had been measured at Roanoke, officially, since Monday morning, with 3 to 7 inches common in and around the Roanoke Valley. Another 1 to 3 inches of rain was forecast through Friday morning.
The weather service expects the Roanoke River to rise to 16.6 feet by midday Thursday. If that happens, it would be the city’s eighth highest crest on record, dating to 1901. By mid-evening Wednesday, the river already had passed 13 feet, flooding the Roanoke River Greenway and several parks along the river.
Water levels are expected to fall below flood stage by Friday afternoon.
The last time the river crested more than 16 feet was in October 2018, when it reached 16.64 feet with the remnants of Hurricane Michael.
The persistent rain is being caused by an upper-level low pressure system that has become nearly stalled west of Virginia, having broken apart from most of the fast-moving flow aloft called the jet stream.
The low is spinning thick moisture off the western Atlantic into the Appalachians, lifted and condensed into rain by riding over cooler air at the surface and also gliding up the steep terrain itself. Rain showers continually redevelop as the moisture is lifted over the higher terrain, and occasional heavier rain bands are also rotated into the region from the south by the upper-level low.
By late Thursday and Friday, the low will finally begin to wobble east and north as it is nudged by weather systems far to the west, gradually making the rain more intermittent, though still heavy at times. It is expected to be mostly east of the region by Saturday, with warmth and sunshine returning for the Memorial Day weekend, though there may be afternoon showers and storms as highs in the 80s evaporate the abundant moisture that has collected on the surface from this week’s rain.
In Roanoke, numerous vulnerable roads have been closed. In Salem, the low-lying bridge across the Roanoke River at Mill Lane has been closed. West Riverside Drive is closed as well between Front Avenue and Eddy Avenue, according to the city.
In Roanoke County, floodwaters have closed off four community parks: Brookside Park, Jae Valley Park, Green Hill Park and Starkey Park. The county said it continues to monitor conditions at other sites.
The persistent precipitation filled up the Carvins Cove Dam reservoir and sent about two feet of water running into its spillway where it flowed onto Carvins Creek.
The 80-feet-tall concrete dam wasn’t in danger but a public notice was issued in keeping with regional response plans, according to the Western Virginia Water Authority.
The next phase of action under regional plans would be triggered by four feet of water overflow which officials don’t expect will be reached. A 2014 study concluded the dam could withstand up to 14 feet of water overflow, officials said.
Water authority staff planned to be on-site monitoring conditions throughout the night.
Roanoke Fire-EMS Swift Water Rescue teams have prepared boats in two locations — one boat at Station No. 6 on Jamison Avenue and two boats at Station No. 5 on Melrose Avenue, according to department spokeswoman Kristen Perdue.
Perdue said additional firefighters and EMS personnel will be brought in to help with extra calls that often accompany a storm or flooding.
“When we have weather events, our call volume increases,” Perdue said. “We have five or six persons who will assist on-duty personnel with that increase.”
Perdue said people should stay indoors and avoid driving if they can. Drivers should heed barricades that block flooded streets.
“We’re going to have a lot of rain, so driving is riskier,” she said. “And do not go around the barricades. Often, people see barricades and they think, ‘That’s not too deep, I can go around it.’ They think the barricade doesn’t apply to them. Well, it does apply to them. It applies to everybody.”
Since Roanoke’s last major flooding, a new flood wall was installed at Carilion Roanoke Memorial Hospital.
“It was put in six months ago, and is a special structural glass. That’s why a lot of folks won’t notice that we put it in front of the hospital,” spokeswoman Hannah Curtis said.
The hospital has closed the entrance on the left side that is nearer to the river. The right-side entrance remains open, but I-beams will be moved into place if needed.
“We are more monitoring the situation on standby, than officially activating yet,” she said.
Staff writers Ralph Berrier Jr., Alicia Petska and Luanne Rife contributed to this report.