Spillway / Overflow Well

The spillway is used to discharge excess water from Sun Moon Lake into the Shuili River. Local residents refer to it as a 'skywell'. The spillway is shaped like a circular tower because water flows most quickly through a circular design. The circular tower-shaped spillway is set at a fixed water level; when the water level is normal, the lake water does not flow into the tower. Once it exceeds the full water level, it automatically flows into the spillway for discharge. The spillway is a funnel-shaped structure with a diameter of 24.39 meters, gradually narrowing from top to bottom, and connects to a tunnel with an inner diameter of 3.48 meters and a total length of 219.93 meters. To adapt to the complex terrain and topography, the tunnel and channels change shapes numerous times, which was also one of the reasons why the Sun Moon Lake Hydropower Project was considered 'the largest hydroelectric power project in the East' at the time. It remains a spectacular attraction to this day. Visitors walking the Shuishae-Xiangshan Trail should not forget to stop and take a look.