Water Pollution
What Is Water Pollution?• Any physical,
biological or chemical
change in water
quality that adversely
affects living
organisms or makes
the water unsuitable
for desired uses.
Pollution Indicators
• 1) Hazardous bacterial levels, dead
fish, or lots of algae
Pollution Indicators
• 2) SERIOUS birth defects in almost
50% of animals studied
• 3) Exotic species present
Pollution Indicators
Point vs Nonpoint Sources
• Point: Discharged to env. via pipes/sewers specific places.
• Non-point: Pollutants entering water from large areas rather than a single point
– Mining wastes
– Agricultural runoff
– Urban runoff
Non-Point
Point
Largest pollutant by volume.
Sedimentation occurs b/c of erosion.
1) Sediment Pollution
• So what if there is more
dirt in the water…
Discuss with your
partner the ecological
problems with placing
sediment in the water.
Create a list!
Ecological Probs 1. Reduces light penetration in aquatic systems (Less PS = Less
Oxygen)
Ecological Probs 2. Transports toxic subs. into
water
Ecological Probs 3. Fills Waterways, Wetlands,
Reservoirs
Ecological Probs 4. Nutrient Loss From Soil =
More fertilizer use
Erosion• Process of soil particles being
removed by wind or water.
• Small particles easily moved.
• Soil contains nutrients!
Keeping Sediment In Place
Vegetate!!
2) Raw Sewage: untreated
material from water pipes
from homes/industry.
Sewage Spill. Guess
Where?
Video:
Sewage
Spill in
SLO!!
• Sewer Lines break releases
pathogens (disease causing agents)
into ground or surface water
• 25,000,000 deaths yearly
• Comes from untreated human wastes and animal wastes
• 2.5 billion lack sanitation
3) Disease-Causing Agents
Case Study: Schistosomiasis• Caused by a flatworm:
lives in snail.
• Host releases eggs from feces into water, eggs hatch, infest snail foot.
• Worm grows inside snail, then swims off snail onto human skin.
• Worm enzymes break down human skin enter. Eats RBC’s.
• Symptoms: ab pain, skin rash, anemia, tired
• Most
serious
water
pollutants
in terms
of health
4) Inorganic Plant Nutrients
•Excess nitrates, phosphates cause
eutrophication-excessive Algal growth
Ex: Red Tide: bloom of
dinoflagellates
• Red Tide at Night
Red Tide
Video
5) Organic Compounds: Oil
Exxon Valdez:
1989, Prince
William Sound
O Cpds: Plastics
Oil Spills
6) Inorganic Chemicals:
Metals
• Heavy metals: Hg, Cadmium, Ni, Pb
• Comes from: Lead pipes, Coal burning (Hg), Mining wastes, Tin, Cu on boat hulls
Case Study: Minamata Japan• 1932 Chisso Corp. made acetaldehyde. Hg: industrial byproduct discharged into
bay.
• 1st: Fish/cats began showing weird behaviors.
• 1956: Humans had
loss of motor
control partly
paralyzed and
contorted bodies.
Chisso Corp. Protesters
• 1963: “Minamata
disease” traced to
Hg from Chisso.
People ate fish w/
Hg.
• Forced to dredge
bay and pay victims
• 1,784 died, 86 mill
in compensation
Have You Ever Wondered Why
Power Plants are Near the
Water?
7) Thermal Pollution• Raising or lowering temp. from
normal levels
• From industrial coolant outflows (to cool electrical power plants)
Thermal Pollution• Cons: Lowers Dissolved Oxygen
levels (O in water)
• Thermal Shock: orgs killed by abrupt
change in temp of water.