Water Quality What is water pollution Water pollution

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Water Quality

Water Quality

What is water pollution? Water pollution is any chemical, physical or biological change in

What is water pollution? Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living that drinks or uses or lives in it.

WATER POLLUTION • Ususally comes from: – Human activities both intentional & unintentional 2

WATER POLLUTION • Ususally comes from: – Human activities both intentional & unintentional 2 categories of water pollution sources: 1. Point Source 2. Non-Point Source

1. Point sources discharge pollutants at specific locations into the water source. Example…through pipelines

1. Point sources discharge pollutants at specific locations into the water source. Example…through pipelines or sewers into the surface water. Examples of point sources are: • • Leaking sewagge pipes, Factories sewage treatment plants underground mines oil wells oil tankers agriculture.

2. Nonpoint sources are sources that cannot be traced to a specific or single

2. Nonpoint sources are sources that cannot be traced to a specific or single site of discharge. *They are the result of wide spread runoff from large areas. Examples of nonpoint sources are: • • • acid deposition from the air Traffic; urban run off chemical and pesticide runoff from farmland Storm sewers pollutants that are spread through rivers pollutants that enter the water through groundwater.

There are many classes of water pollution, here a few… 1. Biodegradeable Wastes 3.

There are many classes of water pollution, here a few… 1. Biodegradeable Wastes 3. Sediment Pollution – Eutrophication 4. Chemical Pollution – Sewage – Disease Causing Agents 2. Heat, Thermal Pollution – Bioaccumulation – Organic/inorganic compounds 5. Ocean Dumping

I. Biodegradable Wastes • This category includes such SOURCES as: – Human / animal

I. Biodegradable Wastes • This category includes such SOURCES as: – Human / animal wastes – Food scraps – Organic materials – Sources of Nutrient Pollution are sewage, septic runoff, livestock waste, fertilizer runoff, detergents, and industrial wastes – Disease-causing agents

Effects of Biodegradable Wastes for water pollution… • If there are excessive nutrients, oxygen

Effects of Biodegradable Wastes for water pollution… • If there are excessive nutrients, oxygen consuming bacteria will mulitpy too rapidly, consuming the oxygen in a stream and making it uninhabitable for some species of fish and other aquatic life. • If bacteria grow too fast, they consume enough oxygen so that virtually everything in the water dies, leaving only anaerobic bacteria creates foul smelling gasses. • Spreading of disease-causing bacteria • Provides nutrients for bacteria to multiply fast • Also can cause Eutrophication…

What is Eutrophication? (part of Biodegradeable wastes) • Naturally-occurring changes that take place in

What is Eutrophication? (part of Biodegradeable wastes) • Naturally-occurring changes that take place in a body of water • Caused Lake Erie to age nearly 15, 000 years between 1950 and 1975 • Nitrates and phosphates from runoff cause the process & From erosions of surrounding lands • Occurs slowly over millions of years. • Human activities can accelerate this process • Increasing the amounts of runoff of nitrates and phosphates will increase the rate of eutrophication

Biodegradeable: What is Sewage? • Wastewater carried off by drains or sewers (from toliets,

Biodegradeable: What is Sewage? • Wastewater carried off by drains or sewers (from toliets, washing machines, showers, etc…) Typically includes: • Water containing human wastes, soaps, detergents, and then is released into water causing a number of pollution problems.

What Harm Does Sewage Cause? --It carries disease causing agents, water polluted with sewage

What Harm Does Sewage Cause? --It carries disease causing agents, water polluted with sewage poses a health threat to the public. • Causes 2 serious environmental problems in the water: 1. Enrichment 2. Oxygen demand

ENRICHMENT… • The fertilization of a body of water, caused by the presence of

ENRICHMENT… • The fertilization of a body of water, caused by the presence of high levels of plant nutrients such as nitrogen and phosphorous • This causes: – Aquatic plants and algae grow faster – May take over / clog waterways – Excessive plants/algae cause a lack of oxygen in the water, because the sewage and other organic materials decomposes into CO 2, water, and other materials by the microorganisms… cellular respiration….

What Harms Does Sewage Cause? 2. Biological Oxygen Demand (BOD): A. Sewage is measured

What Harms Does Sewage Cause? 2. Biological Oxygen Demand (BOD): A. Sewage is measured in terms of its biological oxygen demand (BOD). • BOD is defined as: – The amount of oxygen needed by microorganisms in the water to decompose the waste – Large amount of sewage = High BOD, which robs the water of necessary amounts of dissolved oxygen • When dissolved oxygen levels are low, anaerobic microorganism also produce compounds that have unpleasant odors, further deteriorating the water quality.

BOD • Dissolved oxygen is used by most aquatic organisms • When an aquatic

BOD • Dissolved oxygen is used by most aquatic organisms • When an aquatic ecosystem contains high levels of sewage, the decomposing bacteria use up most of the available oxygen and fish begin to die off

Biodegradeable: Disease-Causing Agents • Municipal wastewater (from cities) usually contains many bacteria, viruses, protozoa,

Biodegradeable: Disease-Causing Agents • Municipal wastewater (from cities) usually contains many bacteria, viruses, protozoa, parasitic worms, and other infectious agents that cause human or animal diseases. • Organisms that cause disease, like below, enter the waterways from domestic sewage and untreated human and animal wastes. • Diseases caused by contaminated food and water include: – Typhoid – Cholera – Bacterial dysentery(diarrhea) – Polio – Hepatitis A

Test for Contaminated Water? • Contaminated water causes about 80% of the diseases in

Test for Contaminated Water? • Contaminated water causes about 80% of the diseases in developing countries – Kills about 10 million people per year. • A good indicator of the quality of water for drinking or swimming is the number of colonies of coliform bacteria present in a 100 -milliliter sample of water. – Coliform bacteria are excreted by the billions from humans and animals.

 • Fecal Coliform Test – A reliable test to indicate if the water

• Fecal Coliform Test – A reliable test to indicate if the water is contaminated with sewage or with disease causing agents in the water – Obtain a sample of water • Filter the bacteria and incubate • Count the # of greenish colonies (E. coli) • Safe drinking water should contain no more than 1 coliform bacterium per 100 ml of water (about ½ a cup). • Safe swimming water should have no more than 200 per 100 ml.

Sewage in Cities • Today wastewater is usually treated before being released into the

Sewage in Cities • Today wastewater is usually treated before being released into the environment • However some viruses and parasites are able to resist chlorine and other water treatment processes. • During heavy rains and floods, sanitary sewers sometimes overflow and run into storm sewers that lead to surface water.

Sewage in Rural Areas • People have to be careful where they locate septic

Sewage in Rural Areas • People have to be careful where they locate septic tanks. If a tank is too near a stream or on a hill, wastewater can leak into the stream or flow into a well downhill. • Wastes from cattle, pigs, & chickens can also be a problem • They contribute disease-causing bacteria and other kinds of pollution

II. Thermal Pollution • Heat can be a deadly water pollutant • An important

II. Thermal Pollution • Heat can be a deadly water pollutant • An important relationship exists between the amount of dissolved oxygen in water and its temperature. – The warmer the water, the less dissolved oxygen • Caused by the dumping of hot water into a body of water – Natural causes: • Hot springs • Shallow ponds in summer – Human causes: • Water used to cool industrial or power plants is discharged into streams, etc…

Effects of Thermal Pollution • Raises the temperature of the body of water •

Effects of Thermal Pollution • Raises the temperature of the body of water • Reduces the amount of dissolved oxygen; which affects the life the water can support • Affects/reduces the diversity of species that can survive in that body of water, which can impact the environmental health of a stream – Some sport fish, such as trout, need cold water with high levels of dissolved oxygen and cannot live in warm water. – Other fish, like carp and suckers, thrive in warm water and can take over habitats from other fish if waters become too warm.

III. Sediment Pollution • Sediment is one of our most destructive water pollutants. •

III. Sediment Pollution • Sediment is one of our most destructive water pollutants. • Sediments are particles suspended in a body of water from erosion and surface run off, that eventually settle out and accumulate on the bottom. – America’s water is polluted by more than one billion tons of sediment annually. • It comes from agricultural lands, forest soils exposed by logging, over grazed rangelands, strip mines, and construction.

 • The damage from sediment pollution is cumulative. As plants and fish die,

• The damage from sediment pollution is cumulative. As plants and fish die, the waterway loses its ability to break down wastes and materials that are naturally washed into it. These materials begin to accumulate and form another source of pollution

Sediment Pollution affects: • Makes the water cloudy (turbidity) and reduces light penetration –

Sediment Pollution affects: • Makes the water cloudy (turbidity) and reduces light penetration – reduces photosynthesis and disrupts aquatic food webs by reducing the number of photosynthesizing organisms (such as plankton and plants). This, in turn, reduces the number of aquatic organisms that feed on those organisms. – As sediments darken the water, it causes the absorption of more solar radiation, raising the water temperature even further. • Disrupts food chains – Sediments can also clog the gills and feeding structures of many aquatic animals, – whether they are benthic organisms (ones that live on the bottom), or swimmers. • Sediments can also carry pesticides, bacteria, and other harmful substances. – Sediment that settles out destroys feeding and spawning grounds of fish. • Can block or clog water flows; fills lakes, artificial reservoirs, stream channels, and harbors.

IV. Chemical Pollution • Usually human-caused • • Modern nations rely on thousands of

IV. Chemical Pollution • Usually human-caused • • Modern nations rely on thousands of organic and inorganic chemicals in industry, agriculture, and the home. They provide many benefits and improve existing processes. But improperly used or disposed of, reasonable safe chemical compounds cause toxic reactions. The effects of such toxics can be short term or long term and are regarded as a major national and international health concern. Includes organic and inorganic chemicals: – Household cleaners – Industrial wastes/discharge – Fertilizers and pesticides that have surface run off – Toxic metals • (mercury, lead, cadmium) – Oil spills

Chemical Pollution • Sources of chemical pollution include: – industrial discharges or accidents in

Chemical Pollution • Sources of chemical pollution include: – industrial discharges or accidents in the transport of chemicals (such as oil spills). It can also come from surface runoff from both urban and rural areas, and transport through the atmosphere. – Roads and parking lots collect toxics such as lead, oil, cadmium (from tires) and other pollutants, which can be washed into streams through storm drains. • These can cause immediate toxic effects as well as long-term effects by accumulating in sediment or in living organisms (remember bioaccumulation). – In agricultural areas, pesticides containing toxic compounds are applied to crops to improve crop quality and increase yields. • Improper application of pesticides, however, creates serious water pollution problems. • Runoff from fields can introduce large amounts of toxics into waterways. – Pesticides can also cause groundwater contamination.

Chemical Pollution • The cost of disposing of toxic chemicals created by industry is

Chemical Pollution • The cost of disposing of toxic chemicals created by industry is high. – There are many federal and state laws that require careful monitoring, storage, and disposal of toxic chemicals. Legislation adopted since the late 1970’s has imposed large fines and jail sentences for people caught illegally dumping toxic wastes. • Household chemicals, such as cleaners, dyes, paints, pesticides, and solvents are a large source of toxic water pollution, especially in urban areas. – Many of these materials are simply poured down drains or flushed down toilets with no regard to their consequences. • A single quart of used motor oil can pollute a quarter of a million gallons of water! • Homeowners may use ten times the amount of pesticides per acre as farmers do.

What is Bioaccumulation? • • • The amount of these toxic chemicals increases and

What is Bioaccumulation? • • • The amount of these toxic chemicals increases and accumulates in the tissues of organisms each step up the food chain. (EX… DDT) There were large amounts of pesticides that were used during the 1960's and 1970's and these chemicals still remain in places like the Lake Superior environment. Although sale of these persistent pesticides is banned, there are still supplies of these poisons on the back shelf in home garages, on farms, in schools, and other community locations. Even though these toxic chemicals are banned in the US and Canada, they are still used in other countries around the world. If they enter the atmosphere when they are sprayed or when they are burned, they can be carried on the wind and deposited in our environments. If we eat food that comes from other countries where these pesticides are still used, we can be exposed to them.

Organic Compounds • Organic compounds are ones that contain carbon (such as oil). •

Organic Compounds • Organic compounds are ones that contain carbon (such as oil). • Most of the organic compounds found in water are synthetic chemicals that are created for human activities. • These include pesticides, solvents, industrial chemicals, and plastics. • These commonly have unusual shapes that are not easily broken down by normal processes. • As a result, they remain in waterways for very long periods of time, and can cause issues in the metabolism and health of aquatic life. – Ex. Oil and plastics

Inorganic Compounds • These include acids, salts, and toxic metals such as mercury and

Inorganic Compounds • These include acids, salts, and toxic metals such as mercury and lead. • A large number of inorganic chemicals come from industrial plants, mines, irrigation runoff, oil drilling, and storm runoff from cities. – Some of these pollutants are toxic to organisms. – High levels of these chemicals can make water unfit to drink, – harm or kill aquatic life, – lower crop yields, – and accelerate corrosion of metals exposed to such water. • Mercury and lead are known to cause cancer and death in organisms.

Organic and Inorganic Compounds Another class of water pollutants is water-soluble inorganic pollutants, such

Organic and Inorganic Compounds Another class of water pollutants is water-soluble inorganic pollutants, such as acids, salts and toxic metals. Large quantities of these compounds will make water unfit to drink and will cause the death of aquatic life. Water can also be polluted by a number of organic compounds such as oil, plastics and pesticides, which are harmful to humans and all plants and animals in the water.

Industrial Wastes: Chemicals • Some factories still release toxic chemicals directly into nearby rivers

Industrial Wastes: Chemicals • Some factories still release toxic chemicals directly into nearby rivers and lakes • In the past: Industries stored toxic wastes in barrels or other containers and buried underground. Over time these containers leaked out, polluting both the soil and the groundwater.

Industrial Wastes: Acid Deposition • When coal, oil, and gasoline are burned, molecules of

Industrial Wastes: Acid Deposition • When coal, oil, and gasoline are burned, molecules of the gases sulfur dioxide and nitrogen oxide are released into the atmosphere. • This reacts with rain forming acid rain. • Acid rain can change the p. H level of a lake killing fish and other wildlife

Inorganic Plant Nutrients • The rich supply of nutrients from fertilizers encourages the growth

Inorganic Plant Nutrients • The rich supply of nutrients from fertilizers encourages the growth of plants and algae in and around nearby bodies of water. – This can “choke out” animal life and the build up of dead plant material can make the water shallower and warmer • Runoff & irrigation water also carry away other pollutants (pesticides) from farm fields.

Industrial Wastes: Thermal Pollution • Occurs when heated water from industrial processes is released

Industrial Wastes: Thermal Pollution • Occurs when heated water from industrial processes is released into waterways • Much of the water in factories is used to cool machinery or metal objects. • Even if it contains no chemicals, the warm water alone can act as a pollutant. • Many water organisms can live in only a narrow range of temperatures.

V. Ocean Dumping • Ocean dumping is the dumping or placing of materials in

V. Ocean Dumping • Ocean dumping is the dumping or placing of materials in designated places in the ocean, often on the continental shelf. • This includes: – garbage, construction and demolition debris, sewage sludge, dredge material, and waste chemicals. • In some cases, ocean dumping is regulated and controlled, while some dumping occurs “accidentally” by ships and tankers at sea, or illegally within coastal waters. – Incineration at sea of organic wastes has been allowed at one time or another both in the United States and in Europe. • An important, but little recognized source of ocean dumping is the elimination of bilge water from ships. – (water that does not drain off the sides of the ship decks drains into the bilge)

Ocean Dumping

Ocean Dumping

California 1958 • Between 1946 and 1970, the US dumped ~107, 000 drums of

California 1958 • Between 1946 and 1970, the US dumped ~107, 000 drums of radioactive wastes • including some 47, 800 in the ocean west of San Francisco • However drums actually litter an area of at least 1, 400 square kilometers/540 square miles, – known as the Farallon Island Radioactive Waste Dump, – which now falls almost entirely within the boundaries of the Gulf of the Farallones National Marine Sanctuary. – The exact location of most drums is unknown. – At least some are corroding.