The Niyodo River rises from the confluence of the Omo and Kuma Rivers. The Omo River, which originates from
Mount Ishizuchi, and the Kuma River, which flows from the Misaka Pass, join together in Mimido (
Kumakōgen, Ehime) to form the Niyodo. The river then flows south, carving a deep valley in the
Shikoku Mountains, and eventually empties into the Pacific Ocean near the cities of
Kōchi and
Tosa.
National Route 33, which connects
Matsuyama and Kōchi, runs parallel to the section from Misaka Pass through Mimido to
Ochi. The river is known for its good water quality. In July 2012, it topped a central government-released national ranking of river water quality.
Damming Dams on the Niyodo River and its tributaries include: •
Odo Dam (administered by the Shikoku Regional Development Bureau) •
Ikadatsu Dam (administered by the Shikoku Regional Development Bureau) • Omo Dam No. 3 (administered by
Shikoku Electric Power) == Tourism ==