1. Water Use and Managment
Chapter 11-2
Water Use and Managment

2. Water Use and Management
When a water supply is polluted or overused, everyone living downstream can be affected.
A shortage of clean, fresh water is a major issue
According to the World Health Organization (WHO) more than 1 billion people lack access to a clean, reliable source of fresh water
Mostly in developing countries

3. Water Use and Management
Most water use  irrigation for agriculture
Availability of fresh water, population size/density , and economic conditions affect how people use water.
Industry water use 19% worldwide
Municipal water use 8% worldwide

4. Residential Water Use
Average person in the USA uses about__________
Average person in India uses only ___________

5. Residential Water Use
In the U.S., only about ½ of residential water use is for activities inside the home, such as drinking and cooking.

6. Residential Water Use

7. Water Treatment Potable:
Water treatment removes elements such as mercury, arsenic, and lead
Found in polluted water, but they can also occur naturally in groundwater.

8. Pathogens are found in water contaminated by sewage or animal feces
Water Treatment
Pathogen:
Pathogens are found in water contaminated by sewage or animal feces
Can be removed with water treatment.
Common water treatment method includes both:

9. Drinking water treatment

10. Industrial water use
Water is used to manufacture goods, to dispose of wastes, and to generate power (19% of total)

11. agricultural water use
Agriculture accounts for 67% of the water used in the world.
Plants require a lot of water to grow
Meat production

12. Many different irrigation techniques are used today.
For example:

13. (efficiency 60% and 80% with surge valves)
Center pivot
(efficiency 80% with low-pressure sprinkler and 90–95% with LEPA sprinkler)
Water usually pumped from underground and sprayed from mobile boom with sprinklers.
Drip irrigation
(efficiency 90–95%)
Above- or below-ground pipes or tubes deliver water to individual plant roots.
Gravity flow
(efficiency 60% and 80% with surge valves)
Water usually comes from an aqueduct system or a nearby river.
Stepped Art
Fig , p. 335

14. Water Management Projects
People often live in areas where surface water is inadequate.
Water management projects (such as dams) are designed to meet these needs.
Brining in water to make a dry area habitable
Creating a reservoir for drinking water
Generating electric power, which then allows people to live and grow crops in desert areas.

15. Water Management Projects
The Colorado River begins as a glacial stream in the Rocky Mountains and quickly grows larger as other streams feed into it.
So much of the river’s water is diverted that the river runs dry before it reaches the Gulf of California.

17. Dams and Reservoirs Dam: Reservoir:
Water from a reservoir can be used for flood control, drinking water, irrigation, recreation, and industry.

18. Dams and Reservoirs Hydroelectric dams:
Flowing water to turn a turbine
Generates electrical energy
About 20% of the world electrical energy is generated this way.

19. Provides irrigation water above and below dam
Flooded land destroys forests or cropland and displaces people
Large losses of water through evaporation
Provides water for drinking
Deprives downstream cropland and estuaries of nutrient-rich silt
Reservoir useful for recreation and fishing
Risk of failure and devastating downstream flooding
Can produce cheap electricity (hydropower)
Reduces down-stream flooding of cities and farms
Disrupts migration and spawning of some fish

21. Water Conservation
Residential
Agricultural (Irrigation)
Industrial
Recycling of cooling water and wastewater, instead of discharging used water into a nearby river

22. Xeriscaping
Example: Southern California

23. Water conservation at home

24. Solutions in future
Two possible solutions are:
Desalination
Transporting Fresh Water