Lesson 2Surface Water

Review: Identify the missing steps of the Water Cycle

Freshwater

• The source of freshwater is mostly from precipitation• Most precipitation returns to the atmosphere through

evaporation• The remaining either

• Becomes runoff

• Soaks into the ground to become groundwater

• If the runoff collects into sheets in a small body of moving water it is a stream

Surface Water

•The land that is drained by a stream is called a watershed.•Smaller watersheds run into larger rivers to form their watersheds.

• The approximate watersheds of the Columbia River, the Colorado River, and the Mississippi River.

What is a river?

• A river is a natural watercourse,

• usually freshwater, flowing

• towards the sea.

• Without the hydrological cycle,

• rivers cannot be formed.

Is this a river?

•Adjacent watersheds are separated by a divide.

•Rainfall on one side if the divide runs into one watershed and rainfall on the other side of the divide runs into the adjacent watershed.•The Continental Divide (Great Divide)separates watersheds that drain into opposite sides of the continent

A small body of standing water is called a pondA larger body of standing water is called a lake.A standing body of water is called a reservoir if it is used for:

Water storageFlood controlThe generation of electricity

Water flows from highlands to lowlands due to the pull of

gravity.

River System (Guess the answers)

River source: The place at which the river begins.

Usually found in mountainous areas or highland.

Tributary: Streams and rivers that join the

main river

River mouth: The

place at which a

river ends into the

sea

Water flows from highlands to lowlands due to the pull of

gravity.

River System (Guess the answers)

River source: The place at which the river begins.

Usually found in mountainous areas or highland.

Tributary: Streams and rivers that join the

main river

River mouth: The

place at which a

river ends into the

sea

RIVER SYSTEM

• Source – the starting point of a river

• Mouth – the ending point of a river

• Drainage Basin –The area drained by a river and its tributaries

RIVER SYSTEM

•Confluence – the point at which a tributary joins the main river

• Watershed – The boundary formed by the edges of the drainage basin