Chapter 20: Water Pollution
20.1 What Are the Causes and Effects of Water Pollution?
Water Pollution
Water pollution: Change in water quality that can harm organisms or make water unfit for human uses
Contamination with chemicals
Excessive heat
Nonpoint sources: Broad, diffuse areas. they are hard to identify and control as well as expensive to clean
Runoff
Point sources: Located at specific places. Easy to identify, monitor, and regulate
Sewage
Leading Causes of Water Pollution
Agriculture activities
Sediment eroded from the lands
Fertilizers and pesticides
Bacteria from livestock and food processing wastes
Industrial facilities
Release inorganic & organic chemicals
EX→ Coal ash (waste from burning coal) – stored in ponds (leak) & dumped into lakes & rivers
Mining
Surface mining disturbs the land-- creates soil erosion & runoff of toxic chemicals
Major Water Pollutants Have Harmful Effects
Infectious disease organisms: contaminated drinking water
The World Health Organization (WHO)
1.6 million people die every year, mostly under the age of 5
Major Water Pollutants and Their Sources
Infectious agents (pathogens)
Effects→causes diseases
Examples→ bacteria, viruses, protozoa, parasites
Sources→ include human and animal wastes
Oxygen demanding wastes
Effects→ deplete dissolved oxygen needed by aquatic species
Examples→ biodegradable animal wastes and plant debris
Sources→ sewage, animal feedlots, food processing facilities, paper mills
Plant nutrients
Effects→ cause excessive growth of algae and other species
Examples→ Nitrates and phosphates
Sources→ sewage, animal wastes, inorganic fertilizers
Organic chemicals
Effects→ Add toxins to aquatic systems
Examples→ oil, gasoline, plastics, pesticides, fertilizers, cleaning solvents
Sources→ Industry, farms, households, mining sites, runoff from streets and parking lots
Inorganic chemicals
Effects→ Add toxins to aquatic systems
Examples→ acids, bases, salts, metal compounds
Sources→ Industry, households, mining sites, runoff from streets, and parking lots
Sediments
Effects→ disrupt photosynthesis, food webs, and other process
Examples→ soil, silt
Sources→ Land erosion from farms and construction and mining sites
Heavy metals
Effects→ cause cancer, disrupt immune and endocrine systems
Examples→ lead, mercury, arsenic
Sources→ unlined landfills, household chemicals, mining refuse, industrial discharge
Thermal
Effects→ make some species vulnerable to disease
Examples→ heat
Sources→ Electric power and industrial plants
Common Diseases Transmitted to Humans through Contaminated Drinking Water
Bacteria
Typhoid fever: diarrhea, severe vomiting, enlarged spleen, inflamed intestine; often fatal if untreated
Chlorea: diarrhea, severe vomiting, dehydration; often fatal if untreated
Bacterial dysentery: diarrhea, bleeding; rarely fatal except in infants without proper treatment
Enteritis: severe stomach pain, nausea, vomiting; rarely fatal
Viruses
Infectious hepatitis (type B): Fever, severe headache, loss of appetite, abdominal pain, jaundice, enlarged liver; rarely fatal but may cause permanent liver damage
Poliomyelitis: Fever diarrhea, backache, sore throat, aches in limbs; can infect the spinal cord and cause paralysis and muscle weakness
Parasitic protozoa
Amoebic dysentery: Severe diarrhea, headache, abdominal pain, chills, fever; if not treated can cause a liver abscess, bowel perforation, and death
Giardiasis: Diarrhea, abdominal cramps, flatulence, belching, fatigue
Cryptosporidium: Severe diarrhea, cramps for up to 3 weeks, and possible death for people with weakened immune systems
Parasitic worms
Schistosomiasis: Abdominal pain, skin rash, anemia, chronic fatigue, and chronic general ill health
Ancylostomiasis: Severe anemia and possible symptoms of bronchial infection
20.2 What Are the Major Water Pollution Problems in Streams and Lakes?
Stream Pollution in More Developed Countries
The 1970s→ Water pollution control laws
Successful water clean-up stories
Ohio Cuyahoga River, U.S.
Thames River, Great Britain
Contamination of toxic inorganic and organic chemicals by industries and mines
Too Little Mixing and Low Water Flow Makes Lakes Vulnerable to Water Pollution
Less effective at diluting pollutants than streams
Stratified layers: Little vertical mixing
Little to no water flow
Can take up to 100 years to change the water in a lake
Biological magnification of pollutants
Eutrophication
Eutrophication: Natural enrichment of a shallow lake, estuary, or slow-moving stream. Caused by runoff into the lake that contains nitrates and phosphates
Oligotrophic lake: Low nutrients, clear water
Cultural eutrophication: Nitrates and phosphates from human sources. Farms, feedlots, streets, parking lots. Fertilized lawns, mining sites, sewage plants
Revisiting Lake Washington and Puget Sound
Severe water pollution can be reversed
Citizen action combined with scientific research
Good solutions may not work forever
Wastewater treatment plant effluents sent into Puget Sound
20.3 Pollution Problems Affecting Groundwater, Other Water Sources
Ground Water Cannot Cleanse Itself Very Well
Common pollutants
Fertilizers and pesticides
Gasoline
Organic solvents
Pollutants dispersed in a widening plume
Slower chemical reactions in groundwater due to
Slow flow
contaminants not diluted
Less dissolved oxygen
Fewer decomposing bacteria
Low temperatures
Groundwater Pollution Is a Serious Hidden Threat in Some Areas
China→ 90% of urban aquifers are contaminated or overexploited
U.S.→ FDA reports of toxins found in many aquifers •
Threats
Gasoline, oil
Nitrate ions
Arsenic
Prevent contamination of groundwater
Cleanup can be very expensive and time-consuming
PUR: chlorine and iron sulfate powder
Using Laws to Protect Drinking Water Quality
1974 U.S. Safe Drinking Water Act: Sets maximum contaminant levels for any pollutants that affect human health
Health scientists: strengthen the law
Water-polluting companies: weaken the law
20.4 What Are the Major Water Pollution Problems Affecting Oceans?
Ocean Pollution Is a Growing and Poorly Understood Problem
2006→ State of the Marine Environment
80% of marine pollution originates on land
Sewage
Coastal areas most affected
Deeper ocean waters
Dilution
Dispersion
Degradation
U.S. coastal waters
Raw sewage
Sewage and agricultural runoff: NO3 and PO4 3-
Harmful algal blooms
Oxygen-depleted zones
The huge mass of plastic in the North Pacific Ocean
Ocean Pollution from Oil
Crude and refined petroleum: Highly disruptive pollutants
The largest source of ocean oil pollution: Urban and industrial runoff from land
1989: Exxon Valdez, oil tanker
2010: BP explosion in the Gulf of Mexico
Volatile organic hydrocarbons: Kill many aquatic organisms
Tar-like globs on the ocean’s surface
Coat animals
Heavy oil components sink
Affect the bottom dwellers
20.5 How Can We Best Deal with Water Pollution?
Reducing Surface Water Pollution from Nonpoint Sources
Agriculture
Reduce erosion
Reduce the number of fertilizers
Plant buffer zones of vegetation
Use organic farming techniques
Use pesticides prudently
Control runoff
Tougher pollution regulations for livestock operations
Deal better with animal waste
Sewage Treatment Reduces Water Pollution
Wastewater or sewage treatment plants
Primary sewage treatment: Physical process
Secondary sewage treatment: Biological process with bacteria
Tertiary or advanced sewage treatment: Special filtering processes and bleaching, chlorination
We Can Improve Conventional Sewage Treatment
Peter Montague: environmental scientist
Remove toxic wastes before the water goes to the municipal sewage treatment plants
Reduce or eliminate the use and waste of toxic chemicals
Use composting toilet systems
Wetland-based sewage treatment systems
There Are Sustainable Ways to Reduce and Prevent Water Pollution
Developed countries: Bottom-up political pressure to pass laws
Developing countries: Little has been done to reduce water pollution
Solutions: Methods for Preventing and Reducing Water Pollution
Prevent groundwater contamination
Reduce nonpoint runoff
Reuse treated wastewater for drinking and irrigation
Find substitutes for toxic pollutants
Work with nature to treat sewage
Practice the three R’s of resource use
Reduce air pollution
Reduce poverty
Slow population growth
Reducing Water Pollution
Fertilize garden and yard plants with manure or compost instead of commercial inorganic fertilizer
Minimize your use of pesticides, especially near bodies of water
Prevent yard wastes from entering storm drains
Do not use water fresheners in the toilet
Do not flush unwanted medicines down the toilet
Do not pour pesticides, paints, solvents, oil, antifreeze, or other products containing harmful chemicals down the drain or onto the ground
Chapter 20: Water Pollution
20.1 What Are the Causes and Effects of Water Pollution?
Water Pollution
Water pollution: Change in water quality that can harm organisms or make water unfit for human uses
Contamination with chemicals
Excessive heat
Nonpoint sources: Broad, diffuse areas. they are hard to identify and control as well as expensive to clean
Runoff
Point sources: Located at specific places. Easy to identify, monitor, and regulate
Sewage
Leading Causes of Water Pollution
Agriculture activities
Sediment eroded from the lands
Fertilizers and pesticides
Bacteria from livestock and food processing wastes
Industrial facilities
Release inorganic & organic chemicals
EX→ Coal ash (waste from burning coal) – stored in ponds (leak) & dumped into lakes & rivers
Mining
Surface mining disturbs the land-- creates soil erosion & runoff of toxic chemicals
Major Water Pollutants Have Harmful Effects
Infectious disease organisms: contaminated drinking water
The World Health Organization (WHO)
1.6 million people die every year, mostly under the age of 5
Major Water Pollutants and Their Sources
Infectious agents (pathogens)
Effects→causes diseases
Examples→ bacteria, viruses, protozoa, parasites
Sources→ include human and animal wastes
Oxygen demanding wastes
Effects→ deplete dissolved oxygen needed by aquatic species
Examples→ biodegradable animal wastes and plant debris
Sources→ sewage, animal feedlots, food processing facilities, paper mills
Plant nutrients
Effects→ cause excessive growth of algae and other species
Examples→ Nitrates and phosphates
Sources→ sewage, animal wastes, inorganic fertilizers
Organic chemicals
Effects→ Add toxins to aquatic systems
Examples→ oil, gasoline, plastics, pesticides, fertilizers, cleaning solvents
Sources→ Industry, farms, households, mining sites, runoff from streets and parking lots
Inorganic chemicals
Effects→ Add toxins to aquatic systems
Examples→ acids, bases, salts, metal compounds
Sources→ Industry, households, mining sites, runoff from streets, and parking lots
Sediments
Effects→ disrupt photosynthesis, food webs, and other process
Examples→ soil, silt
Sources→ Land erosion from farms and construction and mining sites
Heavy metals
Effects→ cause cancer, disrupt immune and endocrine systems
Examples→ lead, mercury, arsenic
Sources→ unlined landfills, household chemicals, mining refuse, industrial discharge
Thermal
Effects→ make some species vulnerable to disease
Examples→ heat
Sources→ Electric power and industrial plants
Common Diseases Transmitted to Humans through Contaminated Drinking Water
Bacteria
Typhoid fever: diarrhea, severe vomiting, enlarged spleen, inflamed intestine; often fatal if untreated
Chlorea: diarrhea, severe vomiting, dehydration; often fatal if untreated
Bacterial dysentery: diarrhea, bleeding; rarely fatal except in infants without proper treatment
Enteritis: severe stomach pain, nausea, vomiting; rarely fatal
Viruses
Infectious hepatitis (type B): Fever, severe headache, loss of appetite, abdominal pain, jaundice, enlarged liver; rarely fatal but may cause permanent liver damage
Poliomyelitis: Fever diarrhea, backache, sore throat, aches in limbs; can infect the spinal cord and cause paralysis and muscle weakness
Parasitic protozoa
Amoebic dysentery: Severe diarrhea, headache, abdominal pain, chills, fever; if not treated can cause a liver abscess, bowel perforation, and death
Giardiasis: Diarrhea, abdominal cramps, flatulence, belching, fatigue
Cryptosporidium: Severe diarrhea, cramps for up to 3 weeks, and possible death for people with weakened immune systems
Parasitic worms
Schistosomiasis: Abdominal pain, skin rash, anemia, chronic fatigue, and chronic general ill health
Ancylostomiasis: Severe anemia and possible symptoms of bronchial infection
20.2 What Are the Major Water Pollution Problems in Streams and Lakes?
Stream Pollution in More Developed Countries
The 1970s→ Water pollution control laws
Successful water clean-up stories
Ohio Cuyahoga River, U.S.
Thames River, Great Britain
Contamination of toxic inorganic and organic chemicals by industries and mines
Too Little Mixing and Low Water Flow Makes Lakes Vulnerable to Water Pollution
Less effective at diluting pollutants than streams
Stratified layers: Little vertical mixing
Little to no water flow
Can take up to 100 years to change the water in a lake
Biological magnification of pollutants
Eutrophication
Eutrophication: Natural enrichment of a shallow lake, estuary, or slow-moving stream. Caused by runoff into the lake that contains nitrates and phosphates
Oligotrophic lake: Low nutrients, clear water
Cultural eutrophication: Nitrates and phosphates from human sources. Farms, feedlots, streets, parking lots. Fertilized lawns, mining sites, sewage plants
Revisiting Lake Washington and Puget Sound
Severe water pollution can be reversed
Citizen action combined with scientific research
Good solutions may not work forever
Wastewater treatment plant effluents sent into Puget Sound
20.3 Pollution Problems Affecting Groundwater, Other Water Sources
Ground Water Cannot Cleanse Itself Very Well
Common pollutants
Fertilizers and pesticides
Gasoline
Organic solvents
Pollutants dispersed in a widening plume
Slower chemical reactions in groundwater due to
Slow flow
contaminants not diluted
Less dissolved oxygen
Fewer decomposing bacteria
Low temperatures
Groundwater Pollution Is a Serious Hidden Threat in Some Areas
China→ 90% of urban aquifers are contaminated or overexploited
U.S.→ FDA reports of toxins found in many aquifers •
Threats
Gasoline, oil
Nitrate ions
Arsenic
Prevent contamination of groundwater
Cleanup can be very expensive and time-consuming
PUR: chlorine and iron sulfate powder
Using Laws to Protect Drinking Water Quality
1974 U.S. Safe Drinking Water Act: Sets maximum contaminant levels for any pollutants that affect human health
Health scientists: strengthen the law
Water-polluting companies: weaken the law
20.4 What Are the Major Water Pollution Problems Affecting Oceans?
Ocean Pollution Is a Growing and Poorly Understood Problem
2006→ State of the Marine Environment
80% of marine pollution originates on land
Sewage
Coastal areas most affected
Deeper ocean waters
Dilution
Dispersion
Degradation
U.S. coastal waters
Raw sewage
Sewage and agricultural runoff: NO3 and PO4 3-
Harmful algal blooms
Oxygen-depleted zones
The huge mass of plastic in the North Pacific Ocean
Ocean Pollution from Oil
Crude and refined petroleum: Highly disruptive pollutants
The largest source of ocean oil pollution: Urban and industrial runoff from land
1989: Exxon Valdez, oil tanker
2010: BP explosion in the Gulf of Mexico
Volatile organic hydrocarbons: Kill many aquatic organisms
Tar-like globs on the ocean’s surface
Coat animals
Heavy oil components sink
Affect the bottom dwellers
20.5 How Can We Best Deal with Water Pollution?
Reducing Surface Water Pollution from Nonpoint Sources
Agriculture
Reduce erosion
Reduce the number of fertilizers
Plant buffer zones of vegetation
Use organic farming techniques
Use pesticides prudently
Control runoff
Tougher pollution regulations for livestock operations
Deal better with animal waste
Sewage Treatment Reduces Water Pollution
Wastewater or sewage treatment plants
Primary sewage treatment: Physical process
Secondary sewage treatment: Biological process with bacteria
Tertiary or advanced sewage treatment: Special filtering processes and bleaching, chlorination
We Can Improve Conventional Sewage Treatment
Peter Montague: environmental scientist
Remove toxic wastes before the water goes to the municipal sewage treatment plants
Reduce or eliminate the use and waste of toxic chemicals
Use composting toilet systems
Wetland-based sewage treatment systems
There Are Sustainable Ways to Reduce and Prevent Water Pollution
Developed countries: Bottom-up political pressure to pass laws
Developing countries: Little has been done to reduce water pollution
Solutions: Methods for Preventing and Reducing Water Pollution
Prevent groundwater contamination
Reduce nonpoint runoff
Reuse treated wastewater for drinking and irrigation
Find substitutes for toxic pollutants
Work with nature to treat sewage
Practice the three R’s of resource use
Reduce air pollution
Reduce poverty
Slow population growth
Reducing Water Pollution
Fertilize garden and yard plants with manure or compost instead of commercial inorganic fertilizer
Minimize your use of pesticides, especially near bodies of water
Prevent yard wastes from entering storm drains
Do not use water fresheners in the toilet
Do not flush unwanted medicines down the toilet
Do not pour pesticides, paints, solvents, oil, antifreeze, or other products containing harmful chemicals down the drain or onto the ground