Water Supply and Water Users

Water• one of the most fascinating

compounds on earth

• necessary ingredient for all living organisms

Water• covers about 70% of the

earth of the earth’s surface

• 340 million cubic miles of water on the planet

Water• 97% is in oceans

• 2% is freshwater

• 1% is frozen in glaciers and icecaps

The water cycle• the amount of water on and

around this planet is fairly constant

• availability of water is not as constant

The water cycle• water is continuously moving

from place to place

• the water cycle is called the hydrologic cycle

The water cycle• powered by solar energy

• heats the water causing it to rise into the atmosphere

• called evaporation

The water cycle• water eventually returns to

the ocean in the form of rain, sleet or snow

• returned water is called meteoric water

The water cycle• if the oceans were not

recharged, their water level would decrease over 40 inches per year

The water cycle• the oceans are the largest

reservoir of water we know

• this water is unsuitable for drinking, agricultural use, or industrial use because of the high salt content

The water cycle• the salt is left behind when

the ocean water evaporates

• once the water has evaporated, it forms clouds

The water cycle• the water then comes back to

the earth as rain, sleet or snow

• clouds may drop water over land or over the ocean

The water cycle• rainwater accounts for only

1% of the total water supply

• rain is vital in keeping the water balance on earth

The water cycle• role of plants and animals in the

cycle

• plants absorb water through their roots and release it through tiny pores in their leaves called stomates

The water cycle• evaporation of water from plants

is called transpiration

• animals also need water for their growth

• promotes chemical activity, regulates temperature

The water cycle• and transports nutrients

through the blood of animals

• 65% of an animals weight is water

The water cycle• surface water

• about 30% of the rainfall in the US falls into out lakes, ponds and streams

The water cycle• this surface water is the most

important element to the conservationist

• used by people over and over as it makes its way toward the ocean

The water cycle• used for agriculture

• industrial

• domestic needs

Pollution• renders much of the water

unsuitable for our needs

Ground water• water that does not either

evaporate or run off - soaks into the earth

Three zones• surface - dry soil accepts water

until saturated

• zone of aeration - empty spaces filled with air, extends from the deepest roots to just above the water table

Three zones• groundwater zone - below zone

of aeration

• water saturated rocks called aquifers

• can equal about 100 years of surface runoff volume

Main components• oceans

• evaporation - transpiration

• plants and animals

• surface water

• ground water

Water users• variation in population densities

• U.S. Population drinks about 100 million gallons of water per day

• only a fraction of water used

Water users• agriculture

• industry

• hydroelectric plants

• fish and wildlife

• recreational and domestic

Agriculture• main use is irrigation

• most common methods include:

• surface and sprinkler techniques

Industry• uses more water than any other

raw material

• only a small part of the water is actually consumed

• used as a medium for other processes

Industry• canning - water is used to clean

product and the containers

• cool ovens

• boil the product

• wash away wastes

Industry• may become part of the product• most water is recycled or

returned to the natural water cycle in a drainage ditch or stream

Industry• paper is made in water

• industry draws about 40 billion gallons of water per day

• water supply - major factor in location of industry

Industry• strong pollution control

methods to recycle water rather than draw from an outside source

Hydroelectric plants• major use of water

• US leads the world in hydroelectric power

• supplies only a small portion of our needs

Hydroelectric Plants• concern is with damming of

rivers

• fish runs are interrupted

• habitat is changed

• puts wildlife in danger

Fish and Wildlife• the way water is handled

affects the fish in the water and the wildlife around the water

Fish and Wildlife• land wildlife, inland birds,

waterfowl

• different species require different types of water

Fish and Wildlife• some fish prosper in cold

mountain streams

• some may prefer fast running rapids

Recreation• boating, water skiing, fishing,

sailing and swimming

• Swimming pools - require a lot of water to keep them in compliance with health regs.

Recreation• frozen water activities

• ice skating, hockey, snowboarding and skiing

Domestic Uses• cooking

• baths or showers

• carry away wastes

• Each American uses more water than any other person in the world

Domestic Uses• In the US each person uses

approximately 150 gallons of water per day

• bath - 3-40 gallons

• shower - 5 gallons per minute

Domestic Uses• Wash clothes - 30 gallons

• flush the toilet - 3 gallons

• water the lawn and garden, wash cars

• fire protection

Use• How wasteful can we be and

still have enough clean water to survive?