1. Water Pollution

2. Distribution of Water Reservoirs
Oceans
Ice Caps and Glaciers 97%
1.725%
Atmosphere
0.01%
Rivers, Lakes,
and Inland Seas
Soil Moisture 0.141%
0.0012%
Ground Water
0.4 – 1.7%

3. World Water Supply
97.200% salt water in the oceans
02.014% ice caps and glaciers
00.600% groundwater
00.009% surface water
00.005% soil moisture
00.001% atmospheric moisture

4. Water Cycle
• Atm.
-Ocean -
Land
• Evap. -
PPT -
Runoff

5. Water Pollution
Two major classifications
• Point Source • Non-point Source
• Single large source Diffuse source or many smaller
• Can localize it to one spot point sources
– Industrial Plants • Automobiles
- Sewage pipes • Fertilizer on fields

6. Water Pollution: Many Forms
• Disease: In developing nations, 80% of diseases are
water-related.
• Synthetic Organic Compounds
• Inorganic Compounds & Mineral Substances such
as Acids, etc.
• Radioactive substances
• Oxygen-demanding wastes
• Plant Nutrients
• Sediments
• Thermal Discharges

7. Acid Precipitation: Acid Rain Effects –
When Air Pollution Aquatic Systems
Becomes Water Pollution
When the pH drops below 6.0
species start to die off.
When one species dies, others
that depend on it may as well

8. Oxygen and Water
• Biochemical Oxygen Demand – What
does this mean?
– Anything in the water that bacteria can
break down.
– Bacteria will use up oxygen in the
water
– Other aerobic organisms will die
• What else can affect the amount of O2 in
the water?
– Temperature
– Speed of water flow
– Roughness of surface
over which water flows

9. Stories about particular pollutant forms: Oil
• Both Point and Nonpoint Sources
• Largest source of oil pollution is pipeline leaks and runoff
– 61% ocean oil pollution river & urban runoff
– 30% intentional discharges from tankers
– 5% accidental spills
from tankers
Stories about particular pollutant
forms: Detergents
The nitrates in fertilizers promote excessive growth of algae and
larger aquatic plants, causing offensive algae blooms and driving
out sport fish.
Phosphates are often thought to culprit, nitrogen is the “limiting
factor” in most aquatic systems.

10. Stories about particular pollutant forms: Sediments
• THE largest form of water pollution
• Erosion is source – we’ve sped up rate of erosion, e.g. during
urban construction can lose up to 43 tons of topsoil/acre/year
• Natural rates of erosion: leads to aquatic succession
Succession in Aquatic Habitats

11. Stories about particular pollutant forms:
thermal pollution
• 26% of all water in U.S. is affected by this
• Up to a point of adding heated water, you can get thermal
enrichment
• Adding more heat,
you get
thermal pollution

12. A special case: Groundwater
• What forms of pollution can affect groundwater?
• All of them except thermal pollution!
• Renewal time of groundwater is important
– Rivers: 12-20 days
– Soil Moisture: 280 days
– Groundwater: 300 years
Groundwater doesn’t stay in one place