Okukubi Dam

Okukubi Dam
Downstream face of the dam in July 2011
Interactive map of Okukubi Dam
Official name億首ダム
CountryJapan
LocationKin, Okinawa
Coordinates26°27′54″N 127°55′54″E / 26.46500°N 127.93167°E / 26.46500; 127.93167
StatusOperational
Construction began2009
Opening dateMarch 2013
Construction cost¥3 billion (US$38.2 million)
OwnersDevelopment and Construction Department, Okinawa General Bureau
Dam and spillways
ImpoundsOkukubi River
Height39 m (128 ft)
Length462 m (1,516 ft)
Elevation at crest29 m (95 ft)
Dam volume339,000 m3 (443,395 cu yd)
Spillway typeLabyrinth weir
Spillway capacity430 m3/s (15,185 cu ft/s)
Reservoir
Total capacity8,560,000 m3 (6,940 acre⋅ft)
Active capacity7,860,000 m3 (6,372 acre⋅ft)
Catchment area14.6 km2 (6 sq mi)
Surface area0.61 km2 (0 sq mi)

The Okukubi Dam (億首ダム) is a trapezoidal cemented, sand and gravel (CSG) dam on the Okukubi River in Kin, Okinawa Prefecture, Japan. Construction began in 2009 and its reservoir was filled by 31 March 2013. It is the first trapezoidal CSG-type to be constructed as a main dam in the world. Its purpose is to provide flood control and water for municipal use along with the irrigation of 70 ha (173 acres) of land.