Topic One (1.1): The Drainage Basin System

Introduction Icon.png Introduction

This topic examines how water moves through the hydrological cycle within the drainage basin system between stores, flows, outputs and underground water.

You will study:

  • Outputs: evaporation, evapotranspiration and river discharge.
  • Stores: interception, soil water, surface water, ground water and channel storage.
  • Flows: above ground – throughfall, stemflow, overland flow and channel flow; below ground – infiltration, percolation, throughflow, groundwater and baseflow.
  • Underground water: water tables, ground water, recharge and springs.

Read & Make Notes Icon.png Read and Make Notes

For this topic, you will need to work through pages 1 to 5 of your textbook, completing the Activities at the end of the Section.

Download Icon.png Download and Print

Download and print out these resources to accompany your notes:

PRINT – Fig 1.2 Drainage Basin Download PRINT – Fig 1.2 Drainage Basin

PRINT – Fig 1.6 Infiltration Surface Download PRINT – Fig 1.6 Infiltration Surface

PRINT – Fig 1.7 Ground Water Aquifer Download PRINT – Fig 1.7 Ground Water Aquifer

Top Tip Icon.png Top Tips

Make sure that you understand the following key points:

  • Flows are directional and it is not random. Some are vertical and some are horizontal, and you need to know which flows are which.
  • Overland flow and surface runoff are the same flow and you can use these two names interchangeably.
  • However, throughfall and throughflow are totally different things despite their similar names!
  • When water becomes groundwater it is still moving, groundwater flow or base flow move water towards the river through the saturated rock. Just because the rock is saturated does not mean water stays still within it!

Glossary Icon.png Key Terms

Add the following key terms with definitions to your glossary.

Download READ – The Drainage Basin System

You may find it easier to put them into alphabetical order if you want them as a table (use a computer so you can add to them later) or if you want to get ahead then put them on flashcards with the word on one side and the definition on the reverse which you can use for revision before your exam.

Consolidate Icon.png Consolidate

Now consolidate your understanding by working through these additional resources.

Important Resources

READ – Clear Explanation of the Hydrological Cycle (Geography.about.com) Links to an external site.

READ – Revise the Basics with this GCSE Level Summary (BBC) Links to an external site.

WATCH – 6-minute Introductory Video to the Water Cycle (YouTube) Links to an external site.

WATCH – A Selection of Very Short Videos on Hydrology (BBC) Links to an external site.

WATCH - The Water Cycle - Drainage Basin Processes Links to an external site.

Optional Resources

WATCH - The Water Cycle - The Importance of Water (MASSOLIT) Links to an external site. 

WATCH - The Water Cycle - Major Global Stores and Transfers of Water (MASSOLIT) Links to an external site.

Quiz Understand Icon.png Quiz

Complete the quiz. If you score less than 90%, try again.

QUIZ - The Drainage Basin System