Water Pollution Chapter 19

1
Water Pollution - Chapter 19
2
Water Pollution - Types

• Water Pollution any chemical, biological, or
  physical change in water quality that has a
  harmful effect on living organisms or makes water
  unsuitable for desired uses.
• Infectious Agents bacteria, viruses, protozoa
• Oxygen Damaging Wastes animal manure and plant
  debris
• Inorganic Chemicals water soluble acids, salts
• Organic Chemicals oil, gasoline, plastics,
  pesticides, cleaning solvents, detergents
• Plant Nutrients nitrates, phosphates, and
  ammonium
• Sediment soil, silt
• Radioactive Materials iodine, radon, uranium,
  cesium, and thorium
• Heat excessive heat

3
Water Pollution - Diseases

• Water Borne Diseases
• Typhoid Fever
• Cholera
• Bacterial Dysentery
• Enteritis
• Infectious hepatitis
• Ameobic dysentery
• Giardiasis
• Schistosomiasis

4
Measuring Water Quality

• Use a variety of methods
• Measuring the amounts of coliform bacteria
  present
• Determining water pollution from oxygen demanding
  wastes and plant nutrients by measuring the
  biological oxygen demand (BOD).
• Using chemical analysis to determine the presence
  of inorganic and organic chemicals that pollute
  water
• Using living organisms as indicator species

5
Point Sources

• Point Sources discharge pollutants at specific
  locations through pipes, ditches, or sewers, into
  bodies of surface water easy to identify,
  monitor, and regulate
• Factories
• Sewage treatment plants
• Active and abandoned underground mines
• Oil tankers

6
Nonpoint Sources

• Nonpoint Sources cannot be traced to any single
  site of discharge
• Large land areas that pollute through runoff,
  subsurface flow, or deposition from the
  atmosphere
• Acid deposition
• Runoff of chemicals into surface water from
  croplands, livestock feedlots, logged forests,
  urban streets, lawns, golf courses, and parking
  lots
• Agriculture nonpoint sources
• Sediments
• Inorganic fertilizers
• Manure
• Salts dissolved in irrigation water
• Pesticides
• Responsible for 64 of the total mass of
  pollutants entering streams
• Responsible for 57 of the pollutants entering
  lakes

7
Climate Change and Water Pollution

• Some areas will get more precipitation and others
  will get less
• More intense downpour will flush more harmful
  chemicals, plant nutrients, and microorganisms
  into the waterways.
• Massive flooding
• Can carry many disease carrying pathogens
• Prolonged drought
• Can reduce river flows that dilute waste
• Increase salinity levels
• Cause infectious diseases to spread more rapidly
  because people lack water to stay clean
• Warmer water temperatures can threaten aquatic
  life by reducing dissolved oxygen levels and
  increase the growth rate of populations of
  harmful bacteria

8
Pollution of Streams

• Rivers have a combination of dilution and
  bacterial decay methods. This works as long as
  pollutants do not overload the streams and
  drought, damming, or diversion do not reduce the
  flow of water.
• Rivers do not eliminate slowly degradable and
  nondegradable pollutants
• Oxygen Sag Curve the curve indicating a
  depletion of dissolved oxygen due to the bacteria
  breaking down the waste and depleting the
  dissolved oxygen
• Biological Oxygen Demand amount of O2 required
• The time needed to recover from waste depends on
• Volume of incoming degradable wastes
• Streams volume
• Streams flow rate
• Streams temperature
• Streams pH level

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Threats to Ecological Services of Streams

• Major threats to ecological services are
• Pollution
• Disruption of water flows and species composition
  by dams
• Channelization
• Diversion of water from rivers for irrigation and
  urban areas
• Overfishing
• Ways to improve water quality
• Require that cities withdraw their drinking water
  downstream rather than upstream this would mean
  that each city would have to clean up its own
  waste outputs rather than passing them downstream
  --- upstream users who have clean water without
  high cleanup costs oppose this approach.

10
Good News About Stream Pollution

• Water pollution control laws have increased the
  number and quality of wastewater treatment plants
  and reduced industry pollution
• Laws have been enacted to prevent the dishcharge
  of industrial wastes into the river and sewage
  systems and to appropriate funds to updgrade
  sewage treatment facilities
• River discharges have decreased increased
  dissolved oxygen levels
• Clean up of the Ohio Cuyahoga River, Thames
  river, Rhine River

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Bad News About Stream Pollution

• Large fish kills
• Drinking water contamination
• There are accidental and deliberate releases of
  toxic inorganic chemicals by rivers and mines
• Malfunctioning sewage treatment plants
• Nonpoint runoff or pesticides and nutrients
• Sewage and industrial wastes is a large problem
  in developing countries

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Pollution Problems of Lakes

• Dilution is less effective
• Little mixing due to layers
• Little flow
• Ponds contain small amounts of water
• More vulnerable to contamination by plant
  nutrients, oil, pesticides, and toxic chemicals
  such as lead, mercury, and selenium
• Toxic chemicals and acids can enter lakes and
  reservoirs from the atmosphere
• As they pass through food webs, they can be
  biologically magnified

13
Eutrophication

• Eutrophication the natural nutrient enrichment
  of lakes caused by the inputs of nutrients and
  silt erosion
• Cultural Eutrophication when urban or
  agricultural runoff caused by human activities
  causes an increase in plant nutrients mostly
  nitrate and phosphate containing effluents
• Nutrient overload can cause
• Dense growth of organisms such as algae,
  cyanobacteria, water hyacinths, and duckweed
• When algae die, decomposition by aerobic bacteria
  depletes dissolved oxygen ? can kill fish and
  other aerobic aquatic animals
• Anaerobic bacteria can take over and produce
  gaseous decomposition which creates a smelly,
  highly toxic hydrogen sulfide and methane
• 1/3 of the medium lakes and 85 of large lakes
  near major population centers have cultural
  eutrophication

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Preventing Eutrophication

• Prevention Methods
• Advanced waste water treatment to remove nitrates
  and phosphates
• Bans or limits on phosphates in household
  detergents other cleaning agents
• Soil conservation and land-use control to reduce
  nutrient runoff
• Cleanup Methods
• Removing excess weeds
• Controlling undesirable plant growth with
  herbicides and algacides
• Pumping air through tanks and reservoirs to avoid
  oxygen depletion

15
Pollution in the Great Lakes

• Contain at least 95 of the fresh surface water
  in the US and 20 of the worlds fresh surface
  water
• Home for about 38 million people --- 30 of
  Canadas population and 14 of the US population
• Receives input from 7 states and much of Ontario
  in Canada
• Less than 1 of the water flows out each year
• Receive large quantities of land runoff with
  acids, pesticides, and other toxic chemicals by
  deposition from the atmosphere
• In 1972 a 20 billion dollar control program
  was carried out.
• What needs to happen
• Ban on the use of chlorine as a bleach in pulp
  and the paper industry
• Ban on all new incinerators in the area
• Ban on discharge into the lakes of 70 toxic
  chemicals

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Why is Groundwater Important?

• Groundwater supplies
• 75 of drinking water in Europe
• 51 in the US
• 32 in Asia
• 29 in Latin America

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Groundwater Pollution

• Groundwater pollution comes from
• Storage lagoons
• Septic tanks
• Landfills
• Hazardous waste dumps
• Deep injection wells
• Stored gasoline, oil, solvents, and hazardous
  wastes underground can corrode and leak
• Pollutants in drinking water high risk health
  problems
• Contamination with petrochemicals (gasoline and
  oil)
• Organic solvents (TCE)
• Pesticides
• Arsenic
• Lead
• Fluoride
• Groundwater cannot clean itself of degradable
  wastes as flowing surface water can because it
  flows so slowly, has much smaller amounts of
  decomposing bacteria, and has cold temperatures
  that slow down the chemical reactions that
  decompose waste

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What is the Extent of Groundwater Pollution?

• We do not know few countries locate, track, and
  test aquifers
• We know more specifics about the contamination in
  the US.

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How Can We Protect Groundwater?

• Aquifers are almost impossible to clean because
  of their enormous volume, inaccessibility, and
  slow movement it is also expensive
• Preventing contamination!
• Monitor aquifers near landills and underground
  tanks
• Require leak detection systems for underground
  tanks used to store hazardous liquids
• Banning or more strictly regulated disposal of
  hazardous wastes in deep injection wells and
  landfills
• Storing hazardous liquids above ground in tanks
  with systems that detect and collect leaking
  liquids

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How Much Pollution Can the Oceans Tolerate?

• Oceans can dilute, disperse, and degrade large
  amounts of raw sewage, sewage sludge, oil, and
  some types of degradable industrial waste,
  especially in deep-water areas
• Some organisms have been resilient to the
  industrial waste, but is it moral to drop there?
• We know less about the deep ocean than about
  outer space
• Dumping would delay prevention
• Would promote further degradation of the earths
  life supporting system

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How Do Pollutants Affect Coastal Areas?

• Coastal areas wetlands, estuaries, coastal
  reefs, and mangrove swamps bear the brunt of
  our inputs of waste into the ocean
• 40 of the worlds population lives on the coast
• 14 of 15 of the worlds largest metro areas are
  near coastal waters
• Coastal populations are growing more rapidly than
  the global population
• Municipal sewage and industrial waste are
  sometimes dumped without treatment
• Causes widespread beach pollution and shellfish
  contamination
• Pollution on European Beaches has dropped
• Recent studies have found human viruses in raw
  sewage, effluent from treatment plants, and
  leaking septic tanks
• ¼ of the people using coastal beaches in the US
  develop ear infections, sore throats and eyes,
  respiratory disease, and GI disease
• Runoff and acid deposition can increase nitrates
  and phosphates which cause harmful algal blooms
  (HABs) red, brown, or green tides depending on
  their color
• Can cause waterborne and airborne toxins that
  damage fisheries
• Kills some fish-eating birds
• Reduce tourism
• Poison seafood
• Creates oxygen-depleted zones dead zones
  because of excessive nonpoint inputs of
  fertilizers and animal wastes from land runoff
  and deposition of nitrogen compounds from the
  atmosphere
• Aquatic life dies or moves elsewhere

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Chesapeake Bay

• Largest estuary in the US
• Population continues to grow
• Removes waste from point and nonpoint sources
• Large pollution sink because it is shallow and
  only 1 is flushed into the Atlantic Ocean
• 1983 Chesapeake Bay Program integrated
  coastal management
• Phosphorus and nitrogen levels have declined
• Population still continues to increase
• Difficulty with funding

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What Pollutants Do We Dump Into the Ocean?

• Barges and ships dump large quanitities of dredge
  spoils material laden with toxic metals scraped
  from the bottoms of harbors and rivers
• Sewage sludge also dumped into oceans --- since
  1992 this has been banned in the US
• Difficult to enforce
• Kills 100,000 marine mammals
• Many countries continue to drop toxic wastes into
  the ocean

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Effects of Oil on Ecosystems?

• Crude and refined petroleum are accidentally or
  deliberately released into the ocean
• Tanker accidents and blowouts at offshore
  drilling rigs
• Offshore wells, washing tankers releasing the
  oily water, pipeline and storage tank leak
• Most oil pollution comes from activities on land
  - waste oil dumped, spilled, or leaked onto the
  land by people
• Effects depend on the type of oil, amount
  released, distance released from shore, time of
  year, weather conditions, average water
  temperature, and ocean currents
• Effects
• Can kill animals right away
• Coat the feathers and fur causes the loss of
  buoyancy and many of them drown or die from loss
  of body heat
• Can smoother bottom-dwelling organisms
• Make aquatic organisms unfit for human
  consumption
• Most can recover within 3 years from crude oil,
  10 years from refined oil

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Cleaning Oil Spills

• Mechanical methods floating booms to contain
  the oil spill or keep it from reaching certain
  areas, skimmer boats to vacuum up some of the oil
  into collection barges, absorbent pans to soak up
  the oil
• Chemical methods using coagulating agents to
  cause floating oil to clump together for easy
  pickup, using dispersing agents to break up oil
  slicks
• Fire can burn off floating oil, but crude oil
  is hard to ignite
• Natural action wind and waves mixes the oil
  with water and bacteria biodegrade some of the
  oil
• Only 12 15 can be recovered from an oil spill

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Protecting Coastal Waters

• Reduce the flow of pollution from land and from
  streams emptying into the ocean
• Integrate prevention of air pollution

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Water Pollution From Nonpoint Sources

• Reduce fertilizer runoff use slow release
  fertilizer and use none on steep land
• Reduce the need for fertilizer by alternating
  plantings between row crops and nitrogen fixing
  plants
• Plant buffer zones of vegetation between
  cultivated fields and surface water
• Reduce pesticide runoff only use pesticide when
  needed and use biological control
• Control runoff and infiltration of manure from
  animal feedlots
• Preserve wetland
• Reduce soil erosion and flooding by reforesting
  wetlands

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Water Pollution From Point Sources - Legal
Approach

• Most developing countries drop 80 90 of their
  untreated sewage into rivers, streams, and lakes
  which are used for drinking water, bathing, and
  washing clothes
• Developed countries purify their waste to some
  degree
• Clean Water Act 1977
• Water Quality Act 1987
• Discharge trading policy to use market forces
  to reduce water pollution cap and trade system

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Strengthen the US Clean Water Act

• Increase funding for nonpoint sources of
  pollution
• Increase monitoring of state programs
• Strengthen programs to prevent and control toxic
  waste pollution
• Prove more funding and authority for integrated
  watershed and airshed planning
• Require states to do a better job monitoring and
  enforcing water pollution laws
• Expand the rights of citizens to bring lawsuits
  to ensure that water pollution laws are enforced
• Halting the loss of wetlands
• Higher standards for restoring wetlands
• Creating new wetlands before filling any natural
  wetlands

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Water in the US

• Water improvements in the US
• Rivers and lakes are more fishable and swimmable
• The amount of topsoil lost has decreased
• More people are served by sewage treatment plants
• Bad News
• Many lakes and rivers are still unsafe for
  fishing, swimming, and other recreational uses
• Hog, poultry, and cattle farm runoff pollutes
  rivers
• Large quantities of illegally dumped waste is put
  into US rivers each year
• Many fish caught are unsae to each
• Less than 2 of the nations streams are healthy
• 40 of the countries surface water and
  groundwater is unsafe for human consumption
• Decrease in wetlands

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The Technological Approach for Dealing with
Pollution

• In rural and suburban areas, sewage from each
  house is discharged into a septic tank.
• 25 of all homes in the US are served by septic
  tanks
• Septic tanks should be cleaned out every 3-5
  years to prevent groundwater pollution
• In urban areas, waterborne wastes run though a
  series of sewer pipes
• Some have separate lines for runoff or storm
  water but combined is cheaper
• When rainwater overflows the combined system, the
  discharged untreated sewage goes directly into
  the surface waters

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Levels of Purification

• Primary Sewage Treatment a mechanical process
  that screens out debris and allows suspended
  solids to settle out as sludge in a settling
  tank.
• Secondary Sewage Treatment a biological process
  where aerobic bacteria remove up to 90 of the
  biodegradable, oxygen-demanding organic wastes
• Some use trickling filters aerobic bacteria
  degrade sewage as it seeps through a bed of
  crushed stones covered with bacteria and protozoa
  
• Some use activated sludge process pumping
  sewage into a large tank and mixing it or several
  hours with bacteria-rich sludge and air bubble to
  spur degradation of microorganisms
• Then, water goes to a sedimentation tank where
  the suspended solids and microorganisms settle
  out as sludge
• Sludge is broken down in an anaerobic digester
  and 1) incinerated 2) dumped into an ocean or
  landfill or 3) applied to land as fertilizer
• Advanced sewage treatment a series of
  specialized chemical and physical processes that
  remove specific pollutants left in the water
  after primary and secondary treatment
• Rarely used because they cost twice as much to
  build and four times as much to operate

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Solutions for Sewage Sludge

• In the US, 9 by weight is converted to compost
  for use as a soil conditioner
• 36 is applied to farmland, forests, golf
  courses, cemeteries, parkland, highway medians,
  and degraded land as fertilizer
• 55 is dumped in conventional landfills or
  incinerated
• can contaminate groundwater or pollute the air
  with toxic chemicals and produces a toxic ash
  buried in landfills
• Using sludge to fertilize crops
• Can cause health problems and lawsuits because of
  harmful bacteria and toxic wastes

34
Is Water Safe to Drink?

• Access to clean water in developing countries is
  up to 68 in 2000 from 30 in 1970
• 1/5 of the people in developing countries do not
  have access to clean drinking water
• People get their water from
• Shallow groundwater wells that are easily
  contaminated
• Nearby polluted riverwater
• Mudholes used by both animals and human
• Must drink contaminated water or buy expensive
  water from street vendors (most of it is
  polluted)
• To give access to clean drinking water, it would
  cost 23 billion and prevent
• 3.4 billion illnesses
• 3.4 million deaths

35
Purifying Drinking Water

• Store surface water in a reservoir and allow
  suspended matter to settle
• Sent to a purification plant and treated
• Water is run through sand filters and activated
  charcoal
• Can use UV light
• Strips of cloth to filter out cholera-producing
  bacteria

36
Protecting Drinking Water

• 54 countries in North America and Europe have
  safe drinking water standards
• U.S. Safe Drinking Water Act of 1974 requires the
  EPA to establish national drinking water
  standards called maximum contaminant levels for
  any pollutant that may have adverse effects on
  human health
• Private wells are not required to meet standards
  because of the cost of testing each well and home
  owners opposition to testing
• 7 million illnesses and 1,200 deaths per year
  from drinking contaminated water

37
Strengthen or Weaken the US Safe Drinking Water
Act

• Strengthened
• Combine at least ½ of the 50,000 water systems
  that serve fewer than 3,300 people with larger
  ones nearby
• Strength and enforce public notification
  requirements about violations of drinking water
• Ban all lead in new plumping pipes, faucets, and
  fixtures
• Weaken
• Elimate national tests of drinking water
• Suspened the requirement that the media be
  advised of water emergencies
• Allow states to give drinking water systems a
  right to violate a certain standards if it cannot
  comply
• Eliminate the requirement that water systems use
  affordable, feasible technology to remove
  cancer-causing contaminants

38
Is Bottled Water the Answer

• Bacteria contaminate ½ of bottled water purchased
  in the US
• Does the water bottling company belong to the
  IBWA International Bottled Water Association
  require testing
• National Sanitation Foundation tests for 200
  chemical and biological contaminants
• Bottled water causes excess trash, toxic gases
  and liquids to be released during the manufacture
  of water bottoms, emission of greenhouse gases
  during the shipping and delivery of bottled water

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Making a Difference - Individuals Matter!

• Reduce and prevent water pollution
• Reduce poverty
• Greater emphasis on keeping groundwater from
  contamination
• Putting more emphasis on preventing nonpoint
  pollution
• Reducing the toxicity or volume of pollutants
• Reusing wastewater instead of discharging it
• Recycling pollutants
• Working with nature to treat sewage
• Integrating government policies for water
  pollution with policies for air pollution,
  agriculture, energy, solid and hazardous wastes,
  climate change, land use, and population