The image is a diagram illustrating a water system with three interconnected bodies of water: a lake, a river, and a lock. The lake is located at the bottom of the image, while the river flows through it. The lock is situated above the lake, and there is a small boat floating on the lake. The lock is connected to the river by a pipe, and the river is connected to the lake by another pipe. The lock is labeled as "Lock" in the image.