| Shizunai River | |
| Name Other: | 静内川 |
| Name Etymology: | Ainu language: Shiputnai — A marsh at the origin of the Ainu or Shuttonai — A marsh with plentiful grapes or Shutnai — A river at the foot of a mountain. |
| Subdivision Type1: | Country |
| Subdivision Name1: | Japan |
| Subdivision Type2: | State |
| Subdivision Name2: | Hokkaidō |
| Subdivision Type3: | Region |
| Subdivision Name3: | Hidaka Subprefecture |
| Subdivision Type4: | District |
| Subdivision Name4: | Hidaka District |
| Subdivision Type5: | Municipality |
| Subdivision Name5: | Shinhidaka |
| Length: | 69.9km (43.4miles) |
| Source Confluence: | Koikakushushibichari River and Koibokushushibichari River |
| Source Confluence Coordinates: | 42.4728°N 142.7514°W |
| Source Confluence Elevation: | 300m (1,000feet) |
| Mouth: | Pacific Ocean |
| Mouth Coordinates: | 42.3297°N 142.3681°W |
| Mouth Elevation: | 0m (00feet) |
| Basin Size: | 683.4km2 |
| Tributaries Left: | ,, Shunbetsu River, Penkeonikemushi River, Ponpanbetsu Creek, Penkebetsusawa River, Porokaunnai River |
| Tributaries Right: | Perari River, Poyoppusawa River, Pisenaisawa River, Ibetsusawa River, Abeunnai River |
is a river in Shinhidaka, Hokkaidō, Japan. The Shizunai River drains from the Hidaka Mountains into the Pacific Ocean.
The Shizunai River was known as Shibuchari[1] and Shibechari. This name was derived from Shipe-ichan, meaning "a salmon spawning place" in Ainu.[2]
The name Shizunai is derived from the Ainu language and has three possible sources:[3]
The Shizunai River flows generally southwest from its headwaters in the Hidaka mountains at the confluence of the Koikakushushibichari and Koibokushushibichari rivers. It flows into, a reservoir created by the Takami Dam. Past the dam, the Shizunai river flows into . Past the Shizunai Dam, the river encounters Futa Dam before leaving the mountains for the flood plain. The river flows past the outlying communities of Shizunai before entering the Pacific Ocean just northwest of Shizunai harbor.
The Shizunai River was designated as a wildlife protection area in 1965. Whooper swans overwinter on the Shizunai River.[2]
The Shizunai River basin was the home of the Ainu leader who led Shakushain's revolt against the Shogunate-era Yamato people, especially the Matsumae clan, in the 1660s. In the Edo period the region was used for gold mining.
From river mouth to source:
From river mouth to source: