What to Expect During Flash Flooding
Raleigh experienced a major rain storm on May 21 with almost four inches of rain falling in an hour and a half. In some areas, two inches of rain fell in 15 minutes. This can cause unexpected flooding throughout the city, especially in areas directly surrounding streams and creeks called the floodplain.
Floodplains are an important part of the creek system. They help improve the quality of Raleigh's waterways by cleaning and storing stormwater runoff. Floodplains also provide a place for rainwater to flow when streams cannot handle any more water. This can cause flooding in areas near Crabtree Creek and Walnut Creek. Properties in the floodplain that may experience repeat flood loss can receive assistance through the Flood Hazard Mitigation Program.
Major storms also can overwhelm the City's storm drainage system when too much water is flowing through pipes at one time. This can lead to infrastructure failures that may impact roadways, properties, and the drainage system.
In situations like this, flooding cannot be completely prevented. However, public safety remains our top priority. Crews clean out debris from stormwater pipes leading up to and after a storm to make sure drains are clear. Staff also proactively lower the lakes with high-hazard dams to reduce the amount of water in the system prior to a storm. In addition, stream gauges are used to monitor stream flow, determine when and if a waterway needs to be lowered, and assess potential flooding risks to the community.
Please pay attention to road closures and evacuations during flash flooding. Barriers and detours are put in place for your safety. Most importantly, emergencies should be reported to 911.