Why are low head dams dangerous to small boats and paddle craft?

Low head dams are particularly hazardous to small boats and paddle craft primarily because of backwash. When water flows over a low head dam, it creates a strong recirculating current downstream known as backwash. This current can trap a boat and its occupants near the dam, making it extremely difficult for them to escape. The force of the water can pin a boat against the structure, posing a significant risk to those on board, as they may be unable to move away from the dangerous area.

Understanding this feature of low head dams is crucial for anyone operating a small boat or paddle craft, as it emphasizes the importance of keeping a safe distance from such structures to avoid the potentially life-threatening consequences of being caught in the backwash.