Chapter 5.2 Water Pollution

Types of Water Pollution When you think of water pollution,

what comes to mind?

Water Pollution Water pollution- the introduction of

chemical, physical, or biological agents into water that degrades the quality of the water and affects the organisms that depend on it.

Point sources- distinct locations that pump waste into a waterway.

Nonpoint sources- diffuse areas such as an entire farming region that pollutes a waterway.

Which of these is Non-Point?

Human Wastewater Water produced by human activities such as

human sewage from toilets and gray water from bathing and washing clothes or dishes.

Three reasons scientists are concerned about human wastewater:

Oxygen-demanding wastes like bacteria that put a large demand for oxygen in the water

Nutrients that are released from wastewater decomposition can make the water more fertile causing eutrophication (on next slide)

Wastewater can carry a wide variety of disease-causing organisms.

Eutrophication Eutrophication is an abundance of fertility to

a body of water - caused by an increase in nutrients, such as fertilizers.

Eutrophication can cause a rapid growth of algae which eventually dies, causing the microbes to increase the BOD.

Common Diseases from Human Wastewater

Cholera

Typhoid fever

Stomach flu

Diarrhea

Hepatitis

The vast majority of surface water on the planet is neither potable (fit for drinking) nor toxic. Approximately 25% of the world’s population has no access to potable water.http://www.youtube.com/watch?v=_R_vpNQ0fJc

Pathogens: disease-causing organisms such as bacteria, viruses and parasitic worms often found in untreated waste water or animal feces.

Resulting Illnesses:

Biological Magnification The accumulation of pollutants at

successive levels of the food chain.

Treatments for Human and Animal Wastewater

Septic systems- a large container that receives wastewater from the house.

(transfer steps into personal diagrams)

Treatments for Human and Animal Wastewater Sewage Treatment Plants- centralized plants in areas with large populations

that receive wastewater via a network of underground pipes.

Heavy Metals and Other Substances that can threaten human Health and the

Environment

Lead

Arsenic

Mercury

Acids

Synthetic compounds (pesticides, pharmaceuticals, and hormones)

Oil Pollution

How do these compare to the BP Oil Spill in the Gulf of Mexico (on Earth Day 2010)?

4.9 million barrels (over 200 million gallons) – many times more than any previous human-caused environmental disaster in history!

Ways to Remediate Oil Pollution Containment using

booms to keep the floating oil from spreading.

Chemicals that help break up the oil, making it disperse before it hits the shoreline (like Dawn dish soap).

Bacteria that are genetically engineered to consume oil

Other Water Pollutants

Solid waste pollution (garbage)

Sedim

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(sa

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Other Water Pollutants

Thermal pollution

INDUSTRIAL COMPOUNDS

A river on fire.  In 1952, the polluted Cuyahoga River in Ohio caught fire after a spark ignited the film of industrial pollution that was floating on the surface of the water. (p.393)

Love Canal• NIAGARA FALLS, N.Y.--

Twenty five years after the Hooker Chemical Company stopped using the Love Canal here as an industrial dump (around 1950), 82 different compounds, 11 of them suspected carcinogens, have been percolating upward through the soil, their drum containers rotting and leaching their contents into the backyards and basements of 100 homes and a public school built on the banks of the canal.

Water Laws

Clean Water Act- (1972) supports the “protection and propagation of fish, shellfish, and wildlife and recreation in and on the water”. Issued water quality standards that defined acceptable limits of various pollutants in U.S. waterways.

Water Laws

Safe Drinking Water Act- (1974, 1986, 1996) sets the national standards for safe drinking water. It is responsible for establishing maximum contaminant levels (MCL) for 77 different elements or substances in both surface water and groundwater.