Chap 11, Sect. 3-Water Pollution Objectives

Compare point-source pollution and nonpoint-source pollution

Classify water pollutants by five types Explain why groundwater pollution is difficult to

clean up Describe the major sources of ocean pollution, and

explain the effects of pollution on ecosystems Describe six major laws designed to improve water

quality in the U.S.

DE State Science Standard 8/GLEsGLEs:

  Evaluate decisions about the use of resources in one country and how these decisions can impact the diversity and stability of ecosystems globally.Analyze ways in which human activity (i.e., producing food, transporting materials, generating energy, disposing of waste, obtaining fresh water, or extracting natural resources) can affect ecosystems and the organisms withinRelate a chemical’s properties to its accumulation within organisms, such as PCBs in the fatty tissues of fish.Explain how biomagnification has led to unsafe food supplies, such as mercury accumulation in tuna. Analyze how an understanding of biomagnification has led to the regulation of chemical use and disposal.

Bellringer - Ecolog

Define the term water pollution

Is a cup of coffee polluted water?

Is a muddy stream polluted?

Water Pollution Water Pollution: The introduction of

chemical, physical, or biological agents into water that degrade water quality and adversely affect the organisms that depend on the water.

Two underlying causes of water pollution: Industrialization and rapid human population growth.

Developed vs Developing Developed Countries: Major cause of

water pollution is industrialization

Developing Countries:Major cause of water pollution is sewage and agricultural runoff, spreading diseases.

Point-source Pollution Point-source Pollution: pollution discharged

from a single source. Examples: leaking septic tank, leaking storage

lagoons for polluted waste, unlined landfills, leaking underground storage tanks that contain chemicals or fuels such as gasoline, polluted water from active or abandoned mines, water discharged by industries, public waste-water treatment plants

Non-point-source Pollution Non-point-Source Pollution: comes from

many different sources that are often difficult to identify.

Examples: chemicals added to road surfaces (salt and deicing agents), water runoff from city and suburban streets that may contain oil, gasoline, animal feces, and liter

Non-point-source Examples Pesticides, herbicides, and fertilizer from

residential lawns, golf courses, and farmland Feces and agricultural chemicals from

livestock feedlots Precipitation containing air pollutants Soil runoff from farms and construction sites Oil and gas from personal watercraft

Non-point Pollution Con’t 96% of all polluted bodies of water in

the United States were contaminated by non-point sources

Controlling non-point-source pollution depends to a great extent on public awareness of the effects of activities such as spraying lawn chemicals and using storm drains to dispose of used motor oil

Non-point Pollution Con’t Two cycle engines (Jet Skis,

snowmobiles) are estimated to leak millions of gallons of unburned fuel into ecosystems

20-25% of fuel in two cycle engines fails to combust, and it flushes into water as raw fuel vapor.

Pollutant Types and Sources Pathogens: disease causing organisms,

such as bacteria, viruses, protozoa, and parasitic worms.

Mostly non-point sources; sewage or animal feces, livestock feedlots, and poultry farms; sewage from overburdened wastewater treatment plants

Pollutant Types and Sources Organic Matter: animal and plant

matter remains. Feces, food waste, and debris from food processing plants

Mostly non-point sources

Pollutant Types and Sources Organic chemicals: pesticides, fertilizers,

plastics, gasoline and oil, and other products made from petroleum

Mostly non-point sources: farms, lawns, golf courses, roads, wastewater, unlined landfills, and leaking underground storage tanks

Pollutant Types and Sources Inorganic chemicals: acids, bases, salts,

and industrial chemicals Point-sources and non-point sources Industrial waste, road surfaces,

wastewater, and polluted precipitation

Pollutant Types and Sources Heavy Metals: lead, mercury, cadmium,

and arsenic Point sources and non-point sources Industrial discharge, unlined landfills,

some household chemicals, and mining processes.

Heavy metals can also occur naturally in some groundwater

Pollutant Types and Sources Physical Agents: heat and suspended

solids Point sources and non-point sources Heat from industrial processes and

suspended solids from soil erosion

Pollutant Sources – U.S.

Point Sources 23 million septic-tank systems 190,000 storage lagoons for polluted waste 9,000 municipal landfills About 2 million underground storage tanks

containing pollutants such as gasoline Thousands of public and industrial wastewater

treatment plants

Pollutant Sources – U.S. Non-point Sources

Highway construction and maintenance, including eroding soil and toxic chemicals

Storm-water runoff including oil, gasoline, dog feces, and liter from city and suburban streets

Pesticides from cropland 50 million tons of fertilizer applied to crops,

lawns and golf courses every year 10 million tons of dry salt applied to highways

for snow and ice control every year

Dioxins Dioxin refers to a group of chemicals that

contain chlorine, carbon, oxygen, and hydrogen. They are a byproduct of chemical processes such as paper bleaching.

Dioxins may cause liver and nerve damage, genetic, reproductive, and immune system problems, and many other problems

According to the EPA, dioxins are some of the most toxic chemicals known to science, and they are the most dangerous environmental pollutants in North America -

DuPont Edgemoor

Wastewater: water that contains waste from homes and industry

Wastewater Treatment Plants filter and treat wastewater to make the water clean enough to return to river or lake

Wastewater

Wastewater Most of the wastewater from homes contains

biodegradable material that can broken down by living organisms( animal and plant waste, paper, and soap)

Some household and industrial wastewater and some storm-water runoff contains toxic substances that cannot be removed by standard treatment

Sludge Sludge: The solid material that remains

after treatment. When sludge contains dangerous

concentrations of toxic chemicals, it must be disposed of as hazardous waste

Non-hazardous sludge can be used as fertilizer.

Eutrophication Eutrophication: when lakes and slow

moving streams contain an abundance of nutrients. When organic matter (leaves and animal waste) builds up in a body of water it will begin to decay and decompose. This process of decomposition uses up oxygen. As oxygen is used up, the types of organisms that live in the water change over time

Eutrophication Plants take root in fertile sediment at the

bottom of water. As more plants grow the waters begin to fill in forming a swamp or marsh

Artificial Eutrophication Eutrophication caused by humans is

known as Artificial Eutrophication Inorganic plant nutrients such as

phosphates and nitrogen enter the water from sewage and fertilizer runoff.

Phosphates from laundry detergents can also cause eutrophication

Artificial Eutrophication Phosphates can cause the growth of

large algal blooms,large floating mats of algae. As the algae dies and decompose, most of the dissolved oxygen is used and fish and other organisms suffocate in the oxygen depleted water. ( fish kills)

Thermal Pollution When the temperature of a body of water

increases thermal pollution can result. As water temperature increases, oxygen levels

decrease and can cause massive fish kills Thermal pollution can occur when power

plants and other industries use water in their cooling systems and then discharge the warm water into a lake or stream

Groundwater Pollution Pollutants usually enter groundwater when

polluted water percolates down from the Earth’s surface

Pesticides, herbicides, chemical fertilizers, and petroleum products, as well as leaking underground tanks, are common groundwater pollutants

Other sources include: septic tanks, unlined landfills, and industrial waste lagoons

ppm –(parts per million)

Parts per million water contamination is usually measured in parts per million (ppm)

If the concentration of a pollutant is 5 ppm, there are 5 parts of the pollutant in 1 million parts of water.

If the concentration of gasoline is 3 ppm in 650,000 L of water, how many liters of gasoline are in the water?

ppm solution

(3/1,000,000) x 650,000 L = 1.95 L

Groundwater Clean-up Groundwater pollution is world’s most

challenging environmental problem Even if groundwater pollution were

stopped tomorrow, some ground water would remain for generations to come.

Groundwater recharges are very slow, sometimes taking hundreds to thousands of years

Ocean Pollution Approximately 85% of ocean pollution,

including oil, toxic wastes, and medical wastes, come from activities on land

Most activities that pollute oceans occur near the coasts, where much of the world’s population lives

Sensitive coastal ecosystems (coral reefs, estuaries, and coastal marshes) are most effected by pollution

Eco-Fact Cruise Ship Discharges

In one year, ships dump almost 7 billion kg of trash into the oceans, about 75% from cruise ships

According to most international law, cruise ships are allowed to dump non-plastic waste, including untreated sewage into the oceans

Oil Spills Each year approximately 37 million

gallons of oil from tanker accidents is spilled into the oceans

Tanker oil spills only account for about 5% of oil pollution in the oceans

Most of the oil that pollutes the oceans comes from cities and towns

Oil Spills Every year, as many as 200 million to

300 million gallons of oil enter the ocean from no-point sources on land

That’s almost 10 times the amount of oil spilled by tankers

The road runoff from a coastal city with a population of 5 million in one year could contain as much as a tanker spill

Water Pollution and Ecosystems Many pollutants accumulate in the

environment because they do not decompose quickly

Biomagnification: Each organism along the food chain stores store pollutants in their tissue. So, at each level of the food chain, the level of pollutants increases.

Top of food chain accumulates most toxins

Anti-Pollution Legislation In 1972 the Clean Water Act was passed in the

United States. The stated purpose of the act was to “restore

and maintain the chemical, physical, and biological integrity of the nation’s waters”

Goal: to make all surface water clean enough for swimming and fishing by 1983

Anti-Pollution Legislation This goal was not achieved. The

percentage of lakes and rivers that are fit for swimming and fishing has increased by 30%

Many toxic metals are now removed from wastewater before the water is discharged

Anti-Pollution Legislation 1972: Clean Water Act: goal of making

all surface water safe for swimming and fishing by 1983 – 30% achieved

1972 (Amended 1988) Marine Protection, Research, and Sanctuaries Act: Empowered the EPA to control the dumping of sewage and toxic chemicals in U.S. waters

Anti-Pollution Legislation 1975: Safe Drinking Water Act:

(Amended 1996): introduced programs to protect groundwater and surface water from pollution, strengthened public “right-to know” laws

Anti-Pollution Legislation 1980: Comprehensive Environmental

Response Compensation and Liability Act ( Superfund act): Makes owners, operators, and customers of hazardous waste sites responsible for the cleanup of the sites

Anti-Pollution Legislation 1987: Water Quality Act: Supported

state and local efforts to clean polluted runoff. Established loan funds for new wastewater treatment plants, and created programs to protect major estuaries

Anti-Pollution Legislation 1990: Oil Pollution Act: Attempts to

protect U.S. waterways from oil pollution by requiring that oil tankers in U.S. waters be double-hulled by 2015.