A catchment is the land draining toward a shared outlet. Its river response depends on rainfall, soil, slopes, vegetation and drainage. A hydrograph plots flow against time. Compare peak height with the total area under each illustrative curve: a narrow peak and a broad response tell different stories.
Water and oceans · Discover & try
Why can the same rain make a sharper river peak?
Reading level 2 of 5 · DevelopingChange
Word help
Catchment
The land area draining to a shared outlet.
Hydrograph
A graph of flow or water level over time.
Infiltration
Water entering the ground from the surface.
Watch · Try · Explain
See how it works
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Hypothetical, volume-accounted rainfall–runoff curves; not observed river data or a flood forecast.
What to look for
- Compare hydrograph peak with curve area.
- Keep rainfall fixed while changing paved cover.
- Check that runoff plus other water equals rainfall.
Explain what you noticed
Two new catchments send the same total runoff volume to a stream. One delivers it in a much shorter time. Which response is more likely?
Keep this idea: Runoff amount and travel time both shape a river’s response to rain.
Follow the sources
Source material checked 2026-10-28. Explanations and activities by Nepedia. Source links do not imply endorsement.
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