PowerPoint ® Lecture prepared by Gary A. Beluzo WATER RESOURCES 18

PowerPoint® Lecture prepared by Gary A. Beluzo

WATER RESOURCES

18

Copyright © 2007 McGraw-Hill Publishing Company

STUDENT LEARNING OUTCOMES

• Explain how linkages between surface water and ground water constrain human efforts to increase water supply.

• Explain the effects of overdrafts on water supply in particular and the environment in general.

• Explain how the hydrological cycle contributes to the potential for conflict over water.

• Describe why the ability to buy and sell permits to emit water pollutants could severely reduce the effectiveness of the Clean Water Act.

• Explain how the supply and cleanliness of water supplies affect economic development.

After reading this chapter, students will be able to


The Legend of Ubar

• “Atlantis of the Sands”

• Only source of water for hundreds of kilometers

• Was Ubar just a myth?

• Ubar destroyed in a single night

• If true, the city disappeared between 300 and 500 AD

• NASA satellite images highlighted an ancient road network

• Excavation revealed the entire city

• Water well located on limestone shelf; earthquake swallowed the city.


The Hydrologic Cycle


Infiltration


Ogallala Aquifer

• Aquifer

• Ground water

• Ground water discharge

• Ground water recharge


The Continental Divide• Continental Divide

• Runoff

• Drainage basin or watershed


The Colorado River


Groundwater


Water Use

• Waterworks

• Offstream uses

• Withdrawals

• Discharge

• Consumption


Water Withdrawal in the U.S.


Offstream Water Uses• Municipal Water Use

• Households, businesses, government

• Drinking, sanitation, bathing, and cooking

• Agriculture• Largest user (2/3 of use globally)

• irrigation

• Energy• Thermoelectric power

• Industry• Raw material

• Most water use non-consumptive


Instream Water Use

• Ecological Services

• Water Transport

• Hydroelectric Energy

• Recreation


Threats to Sustainable Supply

• Discharge

• Water pollution

• Absolute water scarcity


Diverting Surface Waters


Mining Ground Water


Saltwater Intrusion


Overdrafts


Domestic and Municipal Sewage

• Sewage

• Pathogens

• Fecal coliform count

• World Health Organization

• Organic wastes

• Chemical Oxygen Demand

• Biochemical Oxygen Demand

• Dissolved Oxygen Deficit


Oxygen Sag Curve


Industrial Water Pollutants

• Sediments

• Heavy metals

• Xenobiotics• Organic compounds synthesized by humans

• Relatively resistant to organic decay


Agricultural Water Pollutants

• Nonpoint pollutants• persistence

• Half-life

• Sorption


Water and Conflict


Market for Water

• Riparian water rights

• Prior appropriation doctrine

• Reasonable use doctrine

• Rule of absolute ownership

• Correlative rights doctrine

• Privatization


Increasing Efficiency


Controlling Water Pollution• Clean Water Act

• Fishable (1983)

• Swimmable (1985)

• Best Practicable Control Technology (by 1977)

• Best Available Technology (by 1989)


Municipal Waste Treatment

• Primary Treatment• Removes large solids using mechanical techniques

• Secondary Treatment• Reduces number of pathogens

• Accelerates decomposition of organic wastes by bacteria

• Tertiary Treatment• Separates undecomposed inorganic nutrients

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PowerPoint ® Lecture prepared by Gary A. Beluzo WATER RESOURCES 18