Wushantou Dam (Chinese: 烏山頭壩; pinyin: Wūshāntóu Bà) 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 100,000 ha (250,000 acres), a tunnel was constructed to divert water from the Zengwun River to fill the reservoir.
In 1974, the Zengwun Dam was completed on the Zengwun 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 50.5 m (166 ft) high and 1,273 m (4,177 ft) long, containing 5,400,000 m³ (7,100,000 cu yd) of material.
The reservoir comprises 9 km² (2,200 acres) and was designed to store 154,160 dam³ (124,980 acre⋅ft) of water.
However, as of 1990 it had been reduced to 83,759 dam³ (67,905 acre⋅ft) due to severe erosion problems upstream.
A concrete overflow spillway is located shortly to the south of the dam, providing a maximum outflow of 1,500 m³/s (53,000 cu ft/s).
The dam sits at the head of a 58 km² (22 sq mi) catchment area, which increases to 539 km² (208 sq mi) when including the portion of the Zengwun River watershed diverted into the reservoir.
Wushantou Dam (Chinese: 烏山頭壩; pinyin: Wūshāntóu Bà) 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 100,000 ha (250,000 acres), a tunnel was constructed to divert water from the Zengwun River to fill the reservoir. In 1974, the Zengwun Dam was completed on the Zengwun 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 50.5 m (166 ft) high and 1,273 m (4,177 ft) long, containing 5,400,000 m³ (7,100,000 cu yd) of material. The reservoir comprises 9 km² (2,200 acres) and was designed to store 154,160 dam³ (124,980 acre⋅ft) of water. However, as of 1990 it had been reduced to 83,759 dam³ (67,905 acre⋅ft) due to severe erosion problems upstream. A concrete overflow spillway is located shortly to the south of the dam, providing a maximum outflow of 1,500 m³/s (53,000 cu ft/s). The dam sits at the head of a 58 km² (22 sq mi) catchment area, which increases to 539 km² (208 sq mi) when including the portion of the Zengwun River watershed diverted into the reservoir.
Wushantou Dam