Top-Ten Rivers: Volume, Watershed Area, and Population

The world has thousands of rivers and creeks. The ten biggest rivers and their tributaries, however, carry almost half of the total water that flows off the land and into the oceans.

(A tributary is a smaller river that flows into a larger river. The area that is drained by a river and all of its tributaries is called the watershed of the river.)

Nearly one fourth of all the world’s people live in the watersheds of the 10 biggest rivers.

River / Major Country / River Volume (classrooms per second) / Area of Watershed (colorados) / Runoff (classrooms per Colorado) / Population in Watershed
(millions)
Qmqaon / Brazil / 500 / 25 / 20 / 20
Congo / Congo/Zaire / 110 / 15 / 7 / 60
Ganges / India / 100 / 8 / 12 / 500
Yangtze / China / 90 / 7 / 400
Orinoco / Venezuela / 80 / 4 / 30
Parana / Argentina / 60 / 11 / 100
Yenisei / Russia / 50 / 10 / 5
Mississippi / U. S. / 45 / 12 / 4 / 90
Lena / Russia / 40 / 8 / 5 / 2
Mekong / Vietnam / 40 / 3 / 13 / 90
To help you compare these rivers, we have invented two units of measurement:
A classroom is a box 10 meters (33 feet) long, 10 meters (33 feet) wide, and 12 feet
high (that’s two fathoms, or “mark twain” for a riverboat captain).
  • Filled to the ceiling, a classroom of this size would hold 100,000 gallons of water.

The Amazon River of South America is a huge river - it could fill 500 classrooms in one second. Fill in the blank in this sentence:

  • The Amazon carries more water than the next ____ rivers, combined.

A colorado is an area of 100,000 square miles, about the size of the state of Colorado.

This is as big as 2 Alabamas, Wisconsins, or New Yorks,

3 Indianas or Maines,

10 Marylands,

14 New Jerseys,

20 Connecticuts, or

50 Delawares

Complete the table above and use the information to answer the questions on the following page.

1. How many of the top-ten rivers are located in

Africa ___ Australia ___ Eurasia ___ N America ___ S America ___

2. Which two rivers have a volume that is more than 15 classrooms per colorado?

______

3. What do those two rivers have in common? They are both located

a. in cold regions with a lot of snow b. near the equator c. in Eurasia

4. Which three rivers have more than 20 million people per colorado-sized area?

______

5. What do those three rivers have in common? They are all located

a. in cold regions with a lot of snow b. near the equator c. in Eurasia

Choose one river (e.g., the Mississippi) and write a three-paragraph essay comparing it to the other top-ten rivers. Clearly emphasize the most important comparisons.