| Wushantou Dam 烏山頭壩 | |
| Coordinates: | 23.2022°N 120.3683°W |
| Location: | Guantian, Tainan, Taiwan |
| Dam Type: | Rock-fill |
| Dam Height: | 56m (184feet)[1] |
| Dam Length: | 1273m (4,177feet) |
| Dam Crosses: | Zengwen River |
| Spillway Type: | free-flow |
| Spillway Capacity: | 1500m3/s |
| Res Name: | Wushantou Reservoir |
| Res Catchment: | 58km2 |
| Res Surface: | 13km2 |
| Res Elevation: | 58.18m (190.88feet) |
| Plant Turbines: | 8.75 + 11.52 MW |
| Plant Capacity: | 20.27 MW |
| Plant Annual Gen: | 84 million KWh |
Wushantou Dam is an embankment dam in Guantian District, Tainan, Taiwan. The dam was designed by Yoichi Hatta and built between 1920 and 1930 during Japanese rule to provide irrigation water for the Chianan Plain as part of the Chianan Irrigation system. Because the natural flow of the Guantian River and other local streams was insufficient for irrigation of a planned 100000ha, a tunnel was constructed to divert water from the Zengwen River to fill the reservoir.[2] In 1974, the Zengwen Dam was completed on the Zengwen River shortly above the diversion tunnel, stabilizing and reducing the sediment load of water flowing into Wushantou Reservoir.
The dam consists of a curved embankment 50.5m (165.7feet) high and 1273m (4,177feet) long, containing 5400000m2 of material. The reservoir comprises 9km2 and was designed to store 154160dam3 of water. However, as of 1990 it had been reduced to 83759dam3 due to severe erosion problems upstream.[3] A concrete overflow spillway is located shortly to the south of the dam, providing a maximum outflow of 1500m3/s. The dam sits at the head of a 58km2 catchment area, which increases to 539km2 when including the portion of the Zengwen River watershed diverted into the reservoir.[4]