(かせん)

かせん
noun
river; rivers and streams
1. river; rivers and streams; waterways
A formal, collective term for rivers and streams. Used primarily in official, administrative, scientific, and news contexts rather than everyday conversation.
河川(かせん)水位(すいい)上昇(じょうしょう)している。
The river's water level is rising.
河川(かせん)(じき)でバーベキューをする(ひと)()えている。
More people are having barbecues on the riverbed.
大雨(おおあめ)による河川(かせん)氾濫(はんらん)(ふせ)ぐため、堤防(ていぼう)整備(せいび)(いそ)がれている。
Improvements to embankments are being expedited to prevent river flooding due to heavy rain.

USAGE:
河川(かせん) is the formal/administrative term for rivers. In everyday speech, (かわ) (river) is used. 河川(かせん) appears in news, government documents, and technical contexts. The compound combines () (large river) and (せん) (river/stream), so it covers waterways of all sizes.

COMMON COLLOCATIONS:

  • 河川(かせん)(じき): riverbed, riverside open space
  • 河川(かせん)氾濫(はんらん): river flooding
  • 河川(かせん)管理(かんり): river management
  • 河川(かせん)工事(こうじ): river construction/maintenance work
  • 一級(いっきゅう)河川(かせん): class-1 river (managed by national government)