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Inspiration Rain


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Title: Inspiration Rain

Chapter 5 Water
All is born of water, all is sustained by
water. Johann Wolfgang von Goethe German Poet
and Dramatist
Powerpoint Templates
5.1 Our Water Resources
  • Much of our water we drink today has been around
    since water first formed on Earth billions of
    years ago
  • Clean, fresh water is essential to life and is
    critical to human health
  • People can survive for more than a month without
    food can only life for a few days without water
  • Two kinds of water are found on EarthFresh water
    (water people can drink, contains little salt)
    and Salt water (water in the oceans, contain
    higher concentrations of dissolved salts)
  • People live longer today because we have clean
    water (to drink, to bathe in, to wash with, to
    irrigate crops and to flush away sewage)

The Water Cycle
  • Earth is called the water planet because of the
    abundance of water (solid, liquid and gas)
  • Water is renewable endlessly circulated through
    the water cycle
  • In the water cycle, water molecules travel
    between Earths surface and the atmosphere.
    (water evaporates, leaves behind salts and other
    impurities water vapor rises into the air gas
    cools and condenses into drops of liquid water
    that form clouds water falls back to Earth and
    replenishes Earths fresh water supply)

Global Water Distribution
  • About 71 of Earths surface is covered by water
  • 97 of that water is salt water, in oceans and
  • 3 is fresh water 77 of that is frozen in
    glaciers and polar icecaps leaving only a
    fraction of the freshwater for human use
  • The water we require for our everyday needs
    (agriculture and drinking) comes mainly from
    lakes and rivers and from a relatively narrow
    zone beneath the Earths surface.

Surface Water
  • Surface water is fresh water on Earths land
    surface (lakes, rivers, streams, wetlands)
    however, that distribution has played a vital
    role in the development of human societies.
  • Surface water makes up a small fraction of
    Earths fresh water
  • Most large cities depend on surface water (fresh
    water that is above ground in lakes, ponds,
    rivers and streams) for drinking water, water to
    grow crops, food such as fish and shellfish,
    power for industry, transportation by boat

River systems
  • All rivers are a result of precipitation rain
    falls, snow melts (from mountains, hills,
    plateaus and plains)
  • The more streams that run into a river, the
    larger the river becomes
  • As streams and rivers move across the land, they
    form a flowing network of water called a river
    system viewed from above, it would look like the
    roots of a tree feeding into the truck
  • The Mississippi, the Amazon and the Nile are
    enormous river systems The Amazon River systems
    is the largest in the world (drains an area
    nearly the size of Europe!)

  • Area of land that is drained by a river is its
    watershed amount of water that falls on a
    watershed varies from year to year
  • Pollution anywhere in a watershed may end up
    polluting a river
  • Lakes provide a more stable water source rapidly
    melting snow and spring and summer rains can
    dramatically increase amount of water in a
  • Communities that depend on rivers for water can
    be severely affected by changes in river systems

  • Most of the fresh water that is available for
    human use cannot be seen---it exists underground
  • Not all rain flows into lakes and streams plants
    use some the water, most seeps underground
  • Water percolates through the soil and down into
    the rocks beneath water stored beneath Earths
    surface in sediment and rock formations is called
  • The water table is where the rocks and soil are
    saturated with water in wet regions, the water
    table may be at the Earths surface and a spring
    of fresh water may flow out onto the ground in
    deserts, the water table may be hundreds of
    meters beneath Earths surface

  • Large amounts of water is found underground in
    rock formations called aquifers (consist of
    rocks, sand, gravel with lots of air space where
    water can accumulate)
  • Aquifers continuously receive water that
    percolates down from the surface (very slow
  • Holds water in the same way a sponge holds water
  • Groundwater can dissolve rock formations
    (limestone) and fill vast caves with water,
    forming underground lakes
  • Important sources of water for many cities and
    for agriculture

Porosity and Permeability
  • Most rock appears to be solid however, many
    kinds of rocks contain small holes, or pore
  • Porosity is the amount of space between the
    particles that make up a rock
  • Water in aquifers is stored in the pore spaces
    and flow from one pore to the next the more
    porous the rock, the more water it holds
  • Permeability is the ability of rock or soil to
    allow water to flow through it (ex gravel)
  • Impermeable - stops the flow of water (clay,
  • Most productive aquifers form in permeable
    materials (sandstone, limestone, layers of sand,

The Recharge Zone
  • Area of land from which groundwater percolates
    down into the aquifer is called the recharge zone
    (through soil and rocks) takes an extremely long
    time to refill an aquifer (tens of thousands of
  • Recharge zones are environmentally sensitive
    areas because pollution can enter the aquifer
    buildings, parking lots (impermeable layers) can
    reduce the amount of water entering an aquifer
  • Communities need to carefully manage recharge

  • If you dig deep enough, you will find water
  • Dig deep into the ground to reach water wells
    may be a more reliable source of water because it
    is filtered and purified as it travels through
    all the layers
  • Height of water tables changes seasonally, so
    wells are dug to extend below the water table
  • If water table falls too low or is removed faster
    than it can be recharged, the well must be dug
  • Problem People are pumping out water faster
    than it can be replaced naturally consequently,
    water levels are dropping rapidly
  • Ogallala Aquifer (western US) is being depleted
  • Some communities who once depended on aquifers
    are now using other sources of fresh water

5.2 Water Use and Management
  • We all live downstream. What does it mean??
    When a water supply is polluted or overused,
    everyone living downstream is affected.
  • Number of people relying on freshwater is
    increasing daily
  • One of Earths most pressing environmental
    problems is a shortage of clean, fresh water
  • According to the World Health Organization, more
    than 1 billion people lack access to a clean
    source of fresh water

Global Water Use
  • Three major uses for water residential,
    agricultural, and industrial
  • Most fresh water worldwide is used to irrigate
  • Availability of fresh water, population size and
    economic conditions affect how people use water
    patterns of water use are not the same everywhere
    (Asia 80, Europe 38)
  • Industrial use accounts for 19 highest
    percentage of use in Europe and North America
  • About 8 is used by households for drinking and

Residential Water Use
  • Major differences in water use throughout the
    world average person in US uses about 300 L (80
    gal) of water per day, half used for inside the
    home for drinking, washing, cooking and personal
    needs, the other half is used outdoors for
    watering lawns and washing cars India uses about
    41 L per day

Water Treatment
  • Most water needs to be treated to make it potable
    (safe to drink) removes elements (mercury,
    arsenic, lead) which are poisonous to humans in
    low concentrations (found in polluted water but
    can also be found naturally in groundwater)
  • Also removes pathogens (organisms that cause
    illness or disease bacteria, viruses, protozoa,
    parasitic worms) found in water contaminated by
    sewage and animal feces
  • Several methods of treating water (both physical
    and chemical treatment)

Industrial Water Use
  • Industry accounts for 19 of water used in the
    world manufacturing goods, disposal of waste,
    generating power
  • Nearly 1000 L of water is needed to produce 1 kg
    of aluminum 500,000 L of water is needed to
    manufacture a car vast amounts of water is used
    to produce computer chips and semiconductors
  • Mostly used to cool power plants (pump water from
    a surface water source, a river or lake, carry
    that water through pipes in a cooling tower, and
    then pump the warmer, generally clean water back
    into the original source)

Agricultural Water Use
  • Agricultural use accounts for 67 of the water
    used in the world nearly 300 L (80 gal) of water
    to produce 1 ear of corn
  • Plants require a lot of water 80 of the water
    used to water plants never reaches the plant
    roots, it evaporates

  • Fertile soil oftentimes found in areas with
    little rainfall so extra water must be supplied
    by irrigation
  • Irrigation is a method used to provide plants
    with water from sources other than direct
    precipitation (earliest forms of irrigation
    involved flooding the fields)
  • Many forms of irrigation are used today, ex
    shallow, water-filled ditches (cotton), high
    pressure overhead sprinklers (inefficient because
    nearly ½ evaporates and never reaches roots
  • Newer, more efficient methods are becoming more

Waste Management Projects
  • For thousands of years, humans have altered
    streams and rivers to make them more useful
  • Nearly 2000 years ago, Romans built aqueducts
    (huge canals from mountains to dry areas) some
    are still used today today, modern engineering
    has allowed water projects to become more complex
  • Water management projects (dams and water
    diversion canals) allow people to live in
    desirable areas where surface water is
    inadequate, or to create reservoirs for
    recreation or drinking water, and to generate
    electric power
  • Piped in water allows people to live and grow
    crops in Southwest US (desert areas)

Water Diversion Projects
  • All or parts of rivers can be diverted into
    canals to provide water to dry regions, ex
    Owens River in California provides drinking water
    to Los Angeles Colorado River provides water to
    7 states
  • Colorado River (flows 1450 miles) begins as a
    glacial stream in the Rocky Mountains, grows
    larger as of the streams feed into it then
    divided to meet the needs of the states so much
    of the water is diverted for irrigation and
    drinking water that it runs dry before it ever
    reaches Mexico and the Gulf of California (only
    makes it there in the wettest years)
  • River water is in high demand disputes over who
    have rights to it occur often (ex Colorado
  • 40 of worlds people rely on water that
    originates in another country conflicts over
    water rights, especially when dams are built
    restricting flow to other countries downstream
    are common
  • Disputes over water rights is likely to become
    more common as populations increase and demand
    for fresh water increases

Dams and Reservoirs
  • Structures built across a river to restrict the
    flow of water downstream and form a reservoir
    (artificial lake formed behind the dam)
  • Water is used for drinking, irrigation,
    manufacturing, flood control, electricity and
  • Hydroelectric dams use the power of flowing water
    to turn a turbine that generates electrical
    energy about 20 of the worlds electricity is
    generated by hydroelectric energy
  • Mixed blessing artificial lake destroys existing
    ecosystems when they are formed and disrupts
    ecosystems downstream when they get less water
    people are displaced from their homes (close to
    50 million people worldwide) farmland below a
    dam is affected as a result of nutrient rich
    sediment being blocked behind the dam rather than
    flowing downstream
  • Dams can malfunction and burst, killing many
    people below the dam
  • No additional dams being built in US but will
    probably continue in developing countries
    (Brazil, India and China)

Water Conservation
  • As water sources become depleted, water becomes
    more expensive
  • Water conservation is one way people will have
    enough water at reasonable prices

Water Conservation in Agriculture
  • Most water loss in agriculture comes from
    evaporation, seepage and runoff
  • Drip irrigation systems offer an initial step
    toward conservation (deliver small amounts of
    water directly to plant roots by using perforated
    tubing, released as needed at a controlled rate)
    managed by computer programs very little loss of
    water to evaporation, seepage or runoff

Water Conservation in Industry
  • Industries have developed water conservation
    plans due to the rising cost for water
  • Most conservation practices involve recycling of
    cooling water and wastewater instead of
    returning water to rivers, businesses recycle the
    water and reuse it (ex production of paper uses
    less than 30 of the water required to produce
    the same amount of paper as 50 years ago)
  • In Denver, Colorado, the city pays small
    businesses to introduce water conservation
    methods saves money for the city and the
    businesses and makes more water available for
    agriculture and residential use.

Water Conservation at Home
  • Households use much less water than agriculture
    and industry, however, people can make a
    difference by changing a few everyday habits
    (using low flow toilets and shower heads, water
    lawns at night, take shorter showers don't run
    water while brushing your teeth, wash only full
    loads of laundry and dishes)
  • Xeriscaping - designing landscapes that require
    minimal water use

Solutions for the Future
  • Conservation alone is not enough to prevent water
    shortages, other sources of fresh water needs to
    be developed
  • Two possible solutions Desalination and
    transporting fresh water

  • Desalination is the process of removing salt from
    saltwater desalination plants heat salt water
    and collect the fresh water that evaporates
  • Some coastal communities rely on the oceans to
    provide fresh water and have built desalination
    plants (Middle East)
  • Desalination consumes a lot of energy, the
    process is too expensive for many nations to

Transporting Water
  • In areas where freshwater resources are not
    adequate, water can be transported from other
    regions (ex Greece, high tourist area, not
    enough fresh water to handle residents and
    tourists so large ships towing enormous plastic
    bags of water travel regularly to the Greek
    Islands to pump fresh water)
  • This is a solution the US is considering, too.
    (Alaska has 1/2 the available fresh water tow
    Alaskan water down the Californian coast)
  • With 76 of Earth's fresh water in frozen
    icecaps, people have considered towing icebergs
    to communities needing fresh water however,
    efficient ways to tow the icebergs is yet to be

5.3 Water Pollution
  • You cannot always determine if water is polluted
    by the way it looks or smells there are
    different forms of water pollution (chemical,
    physical or biological agents)
  • The introduction of these agents can adversely
    affect the water quality and the organisms that
    depend on the water
  • There are two underlying causes of water
    pollution industrialization and rapid human
    population growth
  • In the past 30 years, developed countries are
    making provisions to clean up polluted water
    supplies however, many sources continue to be
    dangerously polluted
  • Water pollution continues to be a big problem in
    developing countries industry is NOT the major
    cause of pollution in those countries
  • Available drinking water in these countries is
    polluted with sewage and agricultural runoff
    (spreading waterborne diseases)
  • People must understand where pollutants come from
    in order to prevent water pollution comes from
    two main sources point and non-point

Point Pollution
  • Pollution that is discharged from a single source
    (ex factory, waste treatment plant, oil tanker)
  • Relatively easy to regulate and control because
    it is easily identified and traced
  • Hard to enforce clean-up

Nonpoint Pollution
  • Comes from many sources rather than from a single
    specific site reaches bodies of water via
    streets and storm sewers (ex homes, lawns,
    farms, highways, also from pesticides,
    fertilizers, animal feces)
  • Extremely difficult to regulate and control
  • Small amounts add up to a huge pollution problem
    96 of polluted bodies of water come from
    nonpoint pollution contamination
  • Public awareness and education will probably be
    the most effective way of reducing nonpoint

  • Water that goes down a drain ends up in a
    wastewater treatment plant
  • Wastewater is water that contains waste from
    homes and industry
  • At a wastewater treatment plant, the water is
    filtered and treated then it is returned to a
    river or lake

Treating Wastewater
  • Home wastewater is biodegradable and can be
    broken down by living organisms (ex toilet and
    kitchen wastewater contains animal and plant
    waste, paper and soap all are biodegradable)
  • However, some home, industrial and storm runoff
    may contain toxic substances that interfere with
    treatment and cannot be removed by the standard

Sewage Sludge
  • By-product of wastewater treatment is sewage
    sludge (solid materials that remains after
    treatment) many contain toxic chemicals
    incinerated and then buried
  • Non-toxic sludge can be used as fertilizer
    (contain plant nutrients) if it is free of
    toxins can be made into bricks when combined
    with clay

  • Disease causing organisms (bacteria, viruses,
    parasitic worms)
  • Can enter water supplies in untreated wastewater
    or animal feces
  • Cholera, hepatitis, typhoid are diseases people
    can get from drinking water containing these
  • Public water supplies are constantly monitored
    for the presence of these pathogens.

Artificial Eutrophication
  • Most nutrients in water come from organic matter
    (leaves, animal waste) it is broken down into
    mineral nutrients by decomposers (bacteria,
  • An overabundance of nutrients can disrupt the
    ecosystem (eutrophic)
  • Eutrophication is a natural process however, the
    addition of inorganic plant nutrients from
    fertilizer runoff and sewage (phosphorous and
    nitrogen, ex laundry detergents, dishwashing
    soap, lawn fertilizers) causes excessive growth
    of algae (algal blooms) which die and when they
    decompose use large amounts of dissolved oxygen
    in the water fish suffocate and die (artificial
  • Some states are now banning phosphate detergents
    others have limited the amount of phosphates in
    the detergents

Section 5.4 Thermal, Groundwater and Ocean
  • Thermal Pollution
  • Excess amount of heat added to the water creates
    thermal pollution from power plants and
    industries use the cool water to circulate in
    their engines and then return the warmed water to
    the lake or river
  • Can kill large quantities of fish when it is too
    warm warm water holds less oxygen depriving
    organisms of oxygen constant influx of warm
    water disrupts the ecosystem
  • Citizens are usually opposed to new construction
    of power plants

Groundwater Pollution
  • Pollutants usually enter groundwater when
    polluted surface water percolates down from
    Earths surface.
  • Likely to plague us for centuries to come
    (petroleum products, pesticides, herbicides,
    fertilizers, and agricultural chemicals are
    common pollutants)
  • Leaking underground storage tanks also contribute
    and are a major source of groundwater pollution
    (located beneath gas stations, farms and homes
    hold products like gasoline and heating fuel as
    they age, they develop leaks which seep into
  • EPA has detected at least 200 hazardous chemicals
    that can seep through the soil and into
    groundwater location of many tanks is unknown so
    they cannot be repaired or replaced until they
    have leaked enough pollutants to be located
    modern underground storage tanks are contained in
  • Other sources of groundwater pollution include
    septic tanks, unlined landfills, industrial
    wastewater lagoons

Cleaning Up Groundwater Pollution
  • One of the most challenging environmental
    problems that the world faces today.
  • Even if we were to stop polluting the groundwater
    today, the water would remain polluted for
    generations to come groundwater recharges very
    slowly (hundreds or thousands of years)
  • Very difficult to decontaminate, water is
    dispersed throughout large areas of rock and
    sand, pollutants cling to materials that make up
    an aquifer

Ocean Pollution
  • How much pollution can the oceans absorb?
    Sailors have reported a river of polystyrene
    that stretches across the ocean from Bermuda to
    the African coast.
  • How long will it take to decompose?
  • Where does it come from?

How Pollutants Get Into Oceans
  • At least 85 of ocean pollution (oil, toxic
    wastes and medical wastes) comes from activities
    on the land (most occurring near the coastline)
    harms sensitive coastal ecosystems like coral
    reefs and estuaries the most
  • Pollution entering rivers flows to the ocean
  • Pollutants are dumped directly into the oceans
    (sludge from wastewater treatment and garbage)

Oil Spills
  • Accidental oil spills, account for only 5 (Exxon
    Valdez, 1989, in Prince William Sound, Alaska
    2001 a fuel-oil spill occurred off the coast of
    the Galapagos Islands)
  • Every year, about 37 million gallons of oil
    spills into the ocean
  • Most oil that pollutes oceans comes from cities
    and towns (200 to 300 million gallons enter from
    nonpoint sources)

Water Pollution and Ecosystems
  • Biological magnification starts at the level
    where a toxin enters the ecosystem bottom
    dwelling organisms enter their bodies-gt eaten by
    small fish -gt eaten by large fish -gt eagle
  • The toxin increases in concentration from one
    tropic level to the next
  • Polluted water may also cause an immediate change
    in the ecosystem killing nearly all things for
    miles downstream
  • Harmful to humans harmful to fish (cancers,
    scale rot, fin rot) or accumulate in fish tissue
    making them dangerous for humans to consume
    (birth defects, reproductive, nervous system,
    liver, kidney damage)

Preventing Ocean Pollution
  • MARPOL prohibits the discharge of oil and
    disposal or abandonment of plastic in oceans or
    coastal water
  • 1974 Helsinki Convention seeks to control
    land-based sources of ocean pollution (toxic
    dumping DDT, cadmium, mercury) and raw
  • US is strengthening its laws 1990 (Marine Mammal
    Protection Act) requiring ships have double hulls
  • Problem It is difficult to monitor every ship in
    the ocean

Who Owns the Oceans?
  • Who has jurisdiction over the oceans? In the
    past, international law allowed nations to
    control the water extending out 3 miles from the
    coast rest of the ocean was high seas and open
    to everyone
  • Now, Law of Sea Treaty extends out 12 nautical
    miles (22 km) or its territorial sea and then
    another 370 km (200 nautical mi) or its exclusive
    economic zone (environmental preservation and
    research) the rest is communal
  • US did not sign treaty (didnt like restrictions
    on seabed mineral mining)

Cleaning Up Water Pollution
  • Congress has passed several laws designed to
    improve water quality in the US
  • In 1969, Cuyahoga River in Cleveland, OH was so
    polluted the river caught on fire and burned for
    several days this event was the major factor in
    the passage of the1972 Clean Water Act
    restore and maintain the chemical, physical and
    biological integrity of the nations waters.
    Goal was to make all surface water clean enough
    for fishing and swimming by 1983 (not achieved,
    but increased by 30)
  • 1972 - Marine Protection, Research and
    Sanctuaries Act (strengthened laws against ocean
  • 1975 Safe Drinking Water Act
  • 1980 Comprehensive Environmental Response
    Compensation and Liability Act
  • 1987 Water Quality Act
  • 1990 Oil Pollution Act (requires oil tankers
    traveling in US waters to have double hulls by
  • They were able to succeed in curbing point
    pollution, but non-point pollution continues to
    be a problem

Bottled Water
  • Many people have opted to drink more bottled
    water than tap because they feel it is safer to
  • Most bottled water comes from the tap that is
    filtered and treated with various chemicals
  • Bottled water is regulated by the government but
    is NOT tested for pollutants as often as the
    public water supply is tested
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