water pollution

Water PollutionWater Pollution

What do you see here?

So much Water Pollution!

What is Water Pollution?• Water pollution occurs when pollutants are

discharged directly into water bodies such as rivers, lakes and seas.

• It also occurs when air and land pollutants are blown by wind or washed by rain into water bodies.

Urban settlements discharge many forms of pollutants into canals, drains and sewer pipes which eventually find their way into the rivers and seas. Sources of pollutants include factories, sewage treatment plants, runoff of chemicals from agricultural plantations and live-stock farms.

What is wrong here?• The people

below are taking care of their home and car,

•but they are doing many things that can damage the environment, especially our water.

Various Various Sources Sources of Water of Water PollutionPollution

Oil Spill

Causes of water pollution

1) Improper disposal of sewage

• Sewage refers to solid or liquid waste that is produced by households or industries. It contains human waste, detergent and chemicals.

• When untreated sewage is discharged into rivers and seas, water pollution occurs.

A sign warns people that the river is polluted with sewage.

Various Various Sources Sources of Water of Water PollutionPollution

Oil Spill

Causes of water pollution1) Improper disposal of sewage (continued)• Industrial waste contains large amounts of toxic

chemicals. Heavy water pollution occurs when untreated industrial waste is irresponsibly discharged into water bodies.

• Sewage is treated at sewage treatment plants to remove its waste products before it is released into water bodies.

Sewage treatment process

Some substances in detergents, sprays and even body lotions and shampoo are non-biodegradable and cannot be removed by sewage treatment processes.

Various Various Sources Sources of Water of Water PollutionPollution

Oil Spill

Causes of water pollution2) Oil spills• Oil spills occur

when the hull of an oil tanker is torn by sharp rocks or when a tanker collides with another ship, causing the oil it is carrying to spill into the sea.

Oil Spills and How it Spreads!

Cases of Oil Spill Cases of Oil Spill in Historyin History

• In 1989, the Exxon Valdez oil tanker went off course, hit rocks, and released large amounts of oil into Alaska’s Prince William Sound.

• This accident cost some US$2.1 billion to clean up.

Photo of black sea.

Photo of tanker oil spill in Prince William Sound, Alaska.

Photo of oil on the beach.

Cases of Oil Spill in HistoryCases of Oil Spill in History

• In 2002, the oil tanker Prestige sank off the coast of Spain and over two years leaked twice as much oil as the Exxon Valdez.

Oil spill in Lebanon caused by bombing of the Jiyyeh power plant on the 15th July 2006.

Cases of Oil Spill in HistoryCases of Oil Spill in History

Slick lawyers

Containmentbooms andfiltration pumps

HOW DO OIL COMPANIES USUALLY DEAL WITH OIL SPILLS?

CHECK ONE:

Clean up the Oil Clean up the Oil Spill ActivitySpill Activity

Cleaning Cleaning up the up the

Oil Spill!Oil Spill!

Various Various Sources Sources of Water of Water PollutionPollution

Oil Spill

Causes of water pollution2) Oil Spillages • However, much more oil is released from other smaller,

day-to-day and less visible activities.• Current studies have shown that most ocean oil pollution

comes from activities on land.• These include normal operation of offshore wells,

washing oil tankers, loading and unloading of oil tankers at ports, and leaks from oil pipelines, refineries and storage tanks.

Causes of water pollution3) Seepage from landfills

Causes of water pollution4) Excess Fertilizers and Pesticides

Littering & Dumping

Fertilizers, Pesticides & herbicides

Seepage from landfills

Oil Spills Sewage

(non-biodegradable)

Water Pollution

Even desert Even desert isles become isles become

dumpsdumps

• When a scientist visited in 1991, he found over 950 pieces of trash in a 1.5-mile (2.4-km) stretch of beach.

• Here's an inventory of the litter

Bird’s Feathers in Bird’s Feathers in Oil Spill ActivityOil Spill Activity

Extent of water pollution1) Endangering plant and animal species• In an oil spill, sea birds cloaked with oil will freeze to

death as their feathers cannot insulate air to protect them from the cold.

• The oil also clogs the birds’ feathers and makes them unable to fly or float on water. They will drown as a result.

Extent of water pollution1) Endangering plant and animal species- Eutrophication• Household waste contains excess nitrogen and

phosphorus which encourage the growth of algae on river and ocean surfaces.

• With the algae covering the water surface, sunlight cannot penetrate and reach the aquatic plants beneath the water surface, causing them to die as photosynthesis cannot occur.

• As a result, aquatic and marine animals that depend on these plants for food will be affected.

Algae covering the surface of a river

What leads to Eutrophication?

What happens when What happens when Eutrophication strikes?Eutrophication strikes?

Example of EutrophicationExample of Eutrophication

Extent of water pollution

2) Negative impact on human health

• Chemicals and toxic metals contaminate shellfish beds, kill spawning fish and accumulate in the tissues of bottom marine feeders.

Our trash kills.Our trash kills.3) Eating Poisonous

marine food• When odds and ends of

life on land-- particularly plastics--end up in the sea, they pose hazards to marine life.

• Animals drown or strangle from getting tangled in discarded or lost fishing gear, or suffer and even die from eating plastics and other garbage.

A northern sea lion, entangled

in an old net

Our trash kills.Our trash kills.

• Biologists who performed an autopsy on an emaciated male whale beached at Sea Side Heights, New Jersey, found this party balloon, ribbon still attached, blocking the animal's digestive tract. courtesy of Marine Mammal Stranding Center

It is all a big food chain!It is all a big food chain!•These chemicals and toxins can be passed on in the food

chain and eventually reach us when we consume the contaminated animals.

Contamination Contamination of water by of water by

sewage sewage bacteriabacteria

Normal Normal CircumstancesCircumstances: Clean Water: Clean Water

Negative impact on Negative impact on

human healthhuman health• People, especially in poor developing countries, can suffer from cholera and typhoid when they drink contaminated water.

Minamata Area

Kyushu

Honshu

Extent of water pollutionEconomic loss• Oil spills threaten the fishing industry and fishermen’s

livelihood.

Extent of water pollutionEconomic loss• Oil spills can also

pollute beaches and affect tourism.

•Needles and syringes washed up onto Long Island and New Jersey beaches during the summer of 1988. •Estimated costs from lost tourism and recreation that year were as high as $3 billion

Extent of water Extent of water pollutionpollution

Economic lossEconomic loss• Cleaning up oil spills requires an

international effort and is a very expensive task.

• Scientists have estimated that no more than 15 percent of the oil from a major oil spill is recovered in a cleanup operation.

• The cheapest way and the most effective approach is to prevent oil pollution.

Littering & Dumping

Fertilizers, Pesticides & herbicides

Seepage from landfills

Oil Spills Sewage

(non-biodegradable)

Water PollutionEutrophicationEndangering Species Negative Effects on

Health

World marine scientists warned at the start of 2001: “Microbiological contamination of the sea has precipitated a health crisis with massive global implications.”