Water, Your Guide to Reliable. Free. 24/7. Download the app now! What to do in Tunnel Traffic Congestion Congestion occurs when demand for a roadway exceeds its capacity. To limit travel delays caused by traffic congestion, try to avoid driving during heavy travel periods, such as during morning and afternoon rush hours. While experiencing congestion, remember to keep your distance! Even if you are moving slowly or traffic stops, keep a good distance between you and the vehicle in front of you.You may also experience traffic stops during traffic delays. Be alert for flagging crews who will be controlling traffic. It is VDOT's mission to ensure your safety on area roadways. Do your part by driving a properly maintained vehicle and by following the rules of the road.