Geography · KS3 Y8 · Rivers & Coasts

Why rivers flood

Why rivers floodFree8:32Heddy Score 3 of 7, below the standard

What you need to know

  • A river's flow comes from surface run-off and slower groundwater flow; a hydrograph shows how discharge responds to rainfall.
  • Heavy seasonal rain, steep slopes and impermeable surfaces send water to the river quickly, raising flood risk.
  • Jakarta floods often because 13 rivers meet in its low delta, sea level is rising, and pumping groundwater makes the land sink.
  • Urbanisation, deforestation, dams and straightened channels speed up run-off and make floods more 'flashy'.
  • Wetlands act like sponges that store and slowly release water, so protecting or rebuilding them reduces flooding.

In this clip

Runs 8:32, from 1:26 to 9:58 of the full video.

Also coversManaging flood risk
Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

135K views · 3.42K likes · CrashCourse 17.3M subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

Uses a vivid case study of Jakarta to show how physical factors and human choices combine to cause floods.

CrashCourse on YouTubechecked 2026-10-22

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