Chapter 1 - Lesson 2
Streams and Rivers, Lakes
Chapter 1
The Earth’s Bodies of Water

• Water covers more than 70% of the Earth
• Water is in the ground and in the air we
breathe
• People, Plants, and Animals all need water
to live
Streams and Rivers page 26
Weathering - is the process of breaking up rocks
into smaller pieces called sediment

• Streams are bodies of water that flow over land in a
channel
• Most streams begin on high ground, among hills or
mountains
• The sources of a stream usually consist of melting
snow/ice or an overflowing lake
• At the end of a stream is the mouth which empties into
another body of water
Streams and Rivers

• Streams can be as small as a shallow brook
• Or as large as a river, the largest and most
important streams
• Most rivers form from many smaller streams
coming together, these are called tributaries
Streams and Rivers
Tributaries – are streams or rivers that flow into
a larger stream or river

• The more tributaries that empty into a river
the larger the river grows
• Together the river and its tributaries are
called a river system
Streams and Rivers
River System – a river and all of its tributaries

• Each continent, except Antarctica, has major rivers and
river systems.
• Africa has the Nile, Asia has the Yangtze, Australia has
the Murray, Europe has the Danube, North America has
the Mississippi, and South America has the Amazon
Streams and Rivers

• The Nile is the Earth’s longest river, it flows from Central
Africa to the Mediterranean Sea
• The Amazon is the Earth’s largest river, carrying more
water than the Mississippi, Nile and Yangtze combined
• River Systems carry or drain water away from the land
around them (drainage basin)
• Rivers are important for many reasons including
drinking, cleaning, travel and trade
Streams and Rivers, Lakes
Drainage Basin – Land drained by a river system

Streams and Rivers
Drainage Basin

• Why did many of the world’s first settlements
form along rivers?
(pg.27)

• Lakes are bodies of water surrounded by land
• The word lake comes from the Greek language meaning
hole because most lakes are holes in the Earth that fill with
water
• Lakes exist on every continent except Antartica
• The greatest amount of lakes exist where there was once
many glaciers such as North America and northern Europe
Lakes

• During the last Ice Age, glaciers gouged huge holes in the
Earth and the holes filled with the water from the melted
glaciers
• Lakes also form where rainwater collects in huge holes
made in other ways
• Crater Lake in Oregon was formed in a crater of an extinct
volcano
Lakes

• Lake Baikal in Russia is the deepest lake on Earth measuring
5,315 feet deep it was formed in a huge crack in the Earth’s
crust called a rift
Lakes
Rift – a long and deep crack in the Earth

• North America has the most lakes out of all of the
continents
• The largest of the North American lakes are the Great Lakes
• One fifth of all of the fresh water on the Earth’s surface is
found in the Great Lakes
Lakes
H – Huron
O – Ontario
M – Michigan
E – Erie
S – Superior

• There are some large bodies of water called seas
that are actually lakes
• The difference is that they are not fresh water, but
salt water and that is why they are called seas
instead of lakes
• The Dead Sea, Sea of Galilee, and the Caspian Sea
are lakes
• The lowest lying lake is the Dead Sea between
Israel and Jordan
• The highest lake is Lake Titicaca in South America
Lakes

Lakes
The Dead Sea

Lakes
Lake
Titicaca

• Not all lakes are made by nature
• Some are man-made and are called resevoirs
• People build dams to control river flooding or to generate
electricity
Lakes
Reservoir – a lake that forms behind a human made dam

Terms to Know
• Reservoir
• Rift
• Drainage basin
• River system
• Tributaries
• How did Ice Age glaciers form lakes in
North America and Europe? (pg. 28)