Largest Drain Hole in the World

Photographs taken from Google Maps.

The Monticello Dam’s is the largest morning glory spillway in the world and its located in in North California. The funnel-shaped outlet next to the dam allows drainage when the lake level is high with a rate of 48,400 cubic feet per second (1370 m³/s) and a diameter at the lip of 72 feet (22 m). The eerie appearance of the morning glory spillway in operation attracts visitors, and when the spillway is dry the outlet downstream is popular with skateboarders.