for be 1st sem. student

1. Water Pollution

2. Types and Sources of Water Pollution
Pg. 535

3. Point and Nonpoint Sources
NONPOINT SOURCES
Urban streets
Suburban
development
Wastewater
treatment
plant
Rural homes
Cropland
Factory
Animal feedlot
POINT
SOURCES

4. Water pollution
 Bacteria,Viruses,Protozoa, Parasitic worms
 Oxygen demanding substances
 Inorganic plant nutrients
 Organic chemicals
 Sediment or suspended matter
 Thermal pollution
 Genetic pollution

5. Rainbow smelt
1.04 ppm
Zooplankton
0.123 ppm
Phytoplankton
0.0025 ppm
Water
0.000002 ppm
Herring gull
124 ppm
Lake trout
4.83 ppm
Herring gull eggs
124 ppm

6. Pollution of Streams
Fig. 20-5

7. Pollution of Lakes
 Eutrophication
Discharge of untreated
municipal sewage
(nitrates and phosphates)
Nitrogen compounds
produced by cars
and factories
Discharge of treated
municipal sewage
(primary and secondary
treatment:
nitrates and phosphates)
Discharge of
detergents
( phosphates)
Natural runoff
(nitrates and
phosphates
Manure runoff
From feedlots
(nitrates and
Phosphates,
ammonia)
Dissolving of
nitrogen oxides
(from internal combustion
engines and furnaces)
Runoff and erosion
(from from cultivation,
mining, construction,
and poor land use)
Runoff from streets,
lawns, and construction
lots (nitrates and
phosphates)
Lake ecosystem
nutrient overload
and breakdown of
chemical cycling
Fig .22.7, p. 499

8. Solutions to better water quality
 Drainage Area Management Plans
 Agriculture plots
 1987 Water Quality Act

9. Fig. 20-12
Water well
Migrating
vapor phase
Contaminant plume moves
with the groundwater
Free gasoline
dissolves in
groundwater
(dissolved
phase)
Groundwater
flow
Water
table
Gasoline
leakage plume
(liquid phase)
Leaking
tank

10. Groundwater Pollution: Causes
Coal strip
mine runoff
Pumping
well
Waste lagoon
Accidental
spills
Groundwater
flow
Confined aquifer
Discharge
Leakage from faulty
casing
Hazardous waste injection well
Pesticides
Gasoline
station
Buried gasoline
and solvent tank
Sewer
Cesspool
septic tank
De-icing
road salt
Water pumping
well Landfill
Fig. 20-11

11. Groundwater Pollution Prevention

12. Fig. 21-10, p. 505
Healthy zone
Clear, oxygen-rich
waters promote growth
of plankton and sea grasses,
and support fish.
Oxygen-depleted zone
Sedimentation and algae
overgrowth reduce sunlight,
kill beneficial sea grasses, use
up oxygen, and degrade habitat.
Red tides
Excess nitrogen causes
explosive growth of
toxicmicroscopic algae,
poisoning fish and
marine mammals.
Farms
Runoff of pesticides, manure, and
fertilizers adds toxins and excess
nitrogen and phosphorus.
Toxic sediments
Chemicals and toxic
metals contaminate
shellfish beds, kill
spawning fish, and
accumulate in the tissues
of bottom feeders.
Construction sites
Sediments are washed into
waterways, choking fish and plants,
clouding waters, and blocking
sunlight.
Urban sprawl
Bacteria and viruses
from
sewers and septic
tanks contaminate
shellfish beds
Oxygen-depleted
zone
Closed
beach
Cities
Toxic metals
and oil from
streets and
parking lots
pollute waters;
Industry
Nitrogen oxides
from autos and
smokestacks,
toxic chemicals,
and heavy metals in
effluents flow into
bays and estuaries.
Closed
shellfish beds
Fig. 20-15

13. Reducing Water Pollution through
Sewage Treatment
 Primary and Secondary sewage treatment.
Figure 20-19

14. Technological Approach: Using
Wetlands to Treat Sewage
(
(
45 centimeter
layer of limestone
gravel coated with
decomposing bacteriaFirst concrete pool Second concrete pool
Sewage
Wetland type
plants
Wetland type
plants
Treated
water

15. Global Outlook: Stream Pollution in
Developing Countries
 Water in many of
central China's rivers
are greenish black from
uncontrolled pollution
by thousands of
factories.
Figure 20-7

16. Case Study: India’s Ganges River: Religion,
Poverty, and Health
 Religious beliefs, cultural traditions, poverty, and
a large population interact to cause severe
pollution of the Ganges River in India.
 Very little of the sewage is treated.
 Hindu believe in cremating the dead to free the soul
and throwing the ashes in the holy Ganges.
 Some are too poor to afford the wood to fully cremate.
 Decomposing bodies promote disease and depletes DO.

17. Case Study: India’s Ganges River: Religion,
Poverty, and Health
 Daily, more than 1
million Hindus in India
bathe, drink from, or
carry out religious
ceremonies in the
highly polluted Ganges
River.

18. Drinking Water Quality
 Safe DrinkingWater
Act
 Maximumcontaminantlevels
 Bottled water

19. Is Bottled Water the Answer?
 Some bottled water is not as pure as tap water
and costs much more.
 1.4 million metric tons of plastic bottles are
thrown away.
 Fossil fuels are used to make plastic bottles.
 The oil used to produce plastic bottles in the U.S. each
year would fuel 100,000 cars.

20. Using Laws to Protect Drinking
Water
 The U.N. estimates that 5.6 million Americans
drink water that does not meet EPA standards.
 1 in 5 Americans drinks water from a treatment
plant that violated one or more safety standard.

21. What Can You Do?
Water Pollution
• Fertilize garden and yard plants with manure or compost
instead of commercial inorganic fertilizer.
• Minimize your use of pesticides.
• Do not apply fertilizer or pesticides near a body of water.
• Grow or buy organic foods.
• Do not drink bottled water unless tests show that your tap
water is contaminated. Merely refill and reuse plastic bottles
with tap water.
• Compost your food wastes.
• Do not use water fresheners in toilets.
• 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.

22.  It is a hard truth to swallow, but nature does
not care if we live or die. We cannot survive
without the oceans, for example, but they
can do just fine without us.