FloodsNC flooding breaks more than a dozen USGS peak records

Just days after Hurricane Matthew made its approach up the east coast, North Carolina is still feeling impacts from the storm as severe flooding has hit much of the central and eastern parts of the state.  

The heavy rains brought by Hurricane Matthew caused flooding that has been intensified due to rain events prior to Matthew that had many rivers across the central and eastern parts of the state already running at above normal streamflow levels. For instance, the community of Spring Lake witnessed period of record flooding in late September, only to have that peak broken again this week.

“We’ve seen peak streamflow records broken for at least 14 sites in North Carolina, said Jeanne Robbins, USGS hydrologist. “But, it is important for people to understand the waters are still rising in some areas, and we could see more records.”

USGS says that period-of-record peaks associated with rainfall from Hurricane Matthew were seen in the Neuse, Cape Fear and Lumber River Basins as of Wednesday afternoon. However, some sites on the Lumber, Tar, Neuse, and Cape Fear Rivers are still rising. The Neuse River near Goldsboro is peaking at about 29.7 feet, which surpassed the Hurricane Floyd peak of 28.85 feet, and downstream the waters are still on the rise. The Neuse River in Kinston, North Carolina, which is a site with records dating back to 1919, is currently reporting a river height of almost 24 feet and the Southeast River Forecast Center is forecasting a crest of 28 feet. If the river was to reach this projected crest, it would surpass the 27.71 feet record previously set by Hurricane Floyd in 1999.

As the water continues to rise across the state, USGS staff will be monitoring rivers in a number of areas including the Tar, Neuse, Cape Fear, and Lumber Rivers.

While river heights are an important measure to document, the discharge or streamflow rate, which is how much water is flowing over an area each second, is what’s most useful in determining the likelihood and severity of flooding.

“The discharge rate is the critical measure for determining how much worse things may get,” said Robbins, a North Carolina native. “Our streamgages and staff members in the field are capturing that vital information, and we’re providing it in real-time to the National Weather Service, U.S. Army Corps of Engineers, and state and local agencies. With that they are able to develop flood forecasts, manage flood control, and do emergency planning necessary to protect lives and property.”

Twenty USGS scientists across the state are in the field making streamflow measurements to calibrate gauges and verify the critical river stage and streamflow data continues to flow in real time.

“We are working with our partners at the Southeast River Forecast Center and the National Weather Service to provide them with the data they need for accurate flood river modeling,” said Robbins. “The USGS is busy doing what we can to make sure our gauges are operational and people have the information they need on how high the rivers are and how much water is flowing. This critical data is vital to assist the forecasters in knowing what is still to come for communities downstream.”

USGS notes that other USGS crews are working in North Carolina to recover storm-tide sensors, which were deployed to record Hurricane Matthew’s coastal impacts. Work is also being done to perform streamgage assessments and repairs as needed. Eight of the nearly 260 streamgages across the state were impacted or damaged by floodwaters, and more may be as the waters continue to rise. Crews are out repairing those they have access to, with six already repaired and back in service.

For more than 125 years, the USGS has monitored flow in selected streams and rivers across the United States. The information is routinely used for water supply and management, monitoring floods and droughts, bridge and road design, determination of flood risk and for many recreational activities.