Yokoyama Dam (横山ダム, Yokoyama damu) is a dam in Ibigawa, in the Gifu Prefecture of Japan.

Yokoyama Dam
LocationIbigawa, Gifu Prefecture, Japan.
Coordinates35°35′35″N 136°27′19″E / 35.59306°N 136.45528°E / 35.59306; 136.45528
Construction began1957
Opening date1964
Dam and spillways
ImpoundsIbi River
Height80.8 m
Length220.0 m
Reservoir
Total capacity43,000,000 m3
Catchment area471.0 km2
Surface area170 hectares