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Chapter 11 - Water
Section 3 Notes
Water Pollution
• Water pollution –
• Two underlying
causes of water
pollution:
– Industrialization
– Rapid Increase In
Human Population
• Industries are not the only contributor to
water pollution. Sewage and agricultural
runoff can cause the spread of eater
pollution.
• Two types of water pollution:
– Point Source Pollution
– Nonpoint Source Pollution
Point Source Pollution
• Definition –
• Leaking septic tank
• Unlined landfills
• Leaking underground storage tanks (gas)
• Water discharge from industries
Nonpoint Source Pollution
• Definition –
• Chemicals added to road surfaces (salt)
• Water runoff from city streets contains oils, gas,
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etc.
Agricultural chemicals and livestock feces
Oil and gas from boats
Clean Up
• Clean up of point or nonpoint is very
difficult.
• Nonpoint is the hardest of the two types
to know where to stop the pollution from
coming from.
• 96% of the polluted bodies in the US were
contaminated by nonpoint pollution.
Pollutant Types and Sources
Type of Pollutant
Organic Chemicals
Agent
disease causing
organisms
animal and plant
matter remains,
feces, food waste
pesticides, fertilizaers,
plastics, detergents,
gas, oil
Inorganic Chemicals
acids, bases, salts,
industrial chemicals
Heavy Metals
lead, mercury,
cadmium, arsenic
mostly nonpoint sources
mostly nonpoint sources: farms,
lawns, golf courses, roads,
unlined gas tanks
point source and nonpoint source:
industries, road surfaces,
wastewater
point source and nonpoint source:
industries, unlined landfills,
household chemcials, mining
processes
Physical Agents
heat and suspended
soilds
point source and nonpoint source:
industries, solids from soil erosion
Pathogens
Organic Matter
Major Sources
mostly nonpoint sources: sewage
and animal feces
Wastewater
• Do you know where water goes after it
flows down the drain in the sink?
• Wastewater –
Treating Wastewater
• Waste Water Treatment Worksheet
• Most of the wastewater from homes
contains biodegradable materials that can
be broken down by living organisms.
• This does not work for towns and cities:
to much waste water.
Sewage Sludge
• Definition –
• Sludge may contain hazardous chemicals
that have to be disposed in a special way.
– Incinerated and buried in a contained landfill
– Very expensive
– Not all sludge is toxic and is mixed with clay
to make bricks
Artificial Eutrophication
• Definition• Most organic matter comes naturally
through the break down of leaves and
animal waste.
• Nutrients are essential to a balanced
ecosystem but overabundance is a bad
situation.
• Fertilizers from farms, lawns, and gardens
are the largest source of nutrients that
cause artificial eutrophication.
• Phosphate in laundry detergents and
dishwasher detergents are a contributing
factor and have be taken out of many
brands.
• Algal Bloom -
Thermal Pollution
• Definition –
• Mostly from industries and their waste
water.
• It can only be a few degree increase and
thermal pollution to happen.
Groundwater Pollution
• Can infiltrate through the ground to
pollute the water.
• Pesticides, herbicides, chemical fertilizers,
and petroleum products are common
groundwater pollutants.
• Leakage of an underground tank is also a
large contributor of groundwater
contamination.
Cleaning Up Groundwater Pollution
• Groundwater pollution is one of the most
challenging environmental problems that
the world faces.
• The ground is a natural filter but it can
only filter so fast and so much pollution.
Ocean Pollution
• Ocean pollution is allowed to a certain
point. Ship scan legally dump wastewater
and garbage overboard in some parts of
the ocean.
• 85% of ocean pollution comes from land
from runoff. Most of the activities that
pollute the oceans occur neat the coast.
EcoFact
• In one year, ships dump almost 7 billion
kg of trash in the ocean. About 75% of of
ship waste comes from cruise ships.
According to most international law, cruise
ships are allowed to dump non-plastic
waste – including untreated sewage, into
the ocean.
Oil Spills
• P.291 Fig 21
• Oil spills have a dramatic effect, but they are
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responsible for only about 5% of oil pollution in
the oceans.
Most of the oil that pollutes the ocean comes
from towns and cities. 200-300 million gallons
of oil enter the ocean from nonpoint sources
each year.
That’s 10 times the amount from oil spilled by
tankers.
Water Pollution and Ecosystems
• Many pollutants accumulate in the
environment because they do not
decompose quickly.
• Biomagnification (or bioaccumulation)-
• Biomagnification is one reason why many
US states limit the amount of fish people
eat from certain bodies of water.
Cleaning Up Water Pollution
• 1972 Clean Water Act (CWA) – set a goal
that all natural surface water fit for fishing
and swimming by 1983 and banned
pollutant discharge into surface water.
• 1972 Marine Protection, Research, and
Sanctuaries Act – EPA could control
dumping of sewage wastes and toxic
chemicals in US waters
• 1975 Safe Drinking Water Act – Protect
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groundwater and surface water from pollution.
1980 Comprehensive Environmental Response
Compensation and Liability Act – makes owners,
operators, and customers of hazardous waste
site responsible for cleanup of the site.
1987 Water Quality Act – established loan funds
to pay for new wastewater treatment plants and
created program to protect estuaries.
1990 Oil Pollution Act – attempts to protect US
waterways from oil pollution by requiring that oil
tankers in US water be double hauled by 2015.