Freshwater Pollution

Water Pollution

Water pollution – chemical, physical or biological things in the water which degrade the quality of the water and affect the organisms dependent on it

Causes: Industrialization Human population boom

Major Types of Water Pollution

Pathogens – disease causing organisms Bacteria, viruses, parasitic worms Sewage

Organic chemicals – pesticides, fertilizer, gasoline, oil, detergents, etc.

Organic matter – biodegradable remains of animals and plants

Inorganic chemicals – acids, salts, toxic metals

Toxic chemicals – poisonous chemicals including heavy metals (lead, mercury), industrial and household chemicals

Physical agents – heat and suspended solids (soil)

Radioactive waste – from power or nuclear processing plants

Major Types of Pollution cont.

Point pollution – discharged from a single source Factory, wastewater treatment plant, oil tanker Easy to regulate and control

Nonpoint pollution – comes from many sources rather than a single specific site Hazardous materials washed into bodies of water Difficult to control 96% of water pollution comes from nonpoint

pollution

Classification of Pollution

Wastewater – water that flows down the drain

Treatment plants remove most but industrial wastewater and toxic substances are harder to get rid of

Creates sludge – solid material that remains after treatment May contain hazardous materials Incinerated or buried in a landfill

Wastewater Treatment Plants

Effects of Water Pollution

Biological magnification – toxic materials work its way through the food chain Soil tainted with toxins enters

producers (sea weed) → lots of seaweed is eaten by small fish → lots of small fish are eaten by one big fish

Big fish has an increased concentration of toxin

Long Term Effects

Biological Magnification

Toxic chemicals can cause cancer, birth defects, damage to reproductive system, nervous system, liver or kidneys

Occurs from drinking polluted water or eating fish with accumulated toxins

Water Pollution and Humans

Toxic chemical or oil spills which instantly kill almost all the living things

Short Term Effects

Artificial Eutrophication

Eutrophic means lots of nutrients Occurs naturally as organisms die

and decompose Artificial – plant nutrients like

phosphorus and nitrogen get into the water Cause algal blooms Algae die and use up oxygen killing fish

Excessive amounts of heat are added to body of water

Water comes from power plants and factories

Too much heat releases oxygen – not enough for fish to survive

Thermal Pollution

Clean Water Act – 1972 – goal to make all surface waters clean enough for fishing and swimming by 1983

Led to more, stricter laws on both national and state level

Personal and industrial progress

Cleaning Up Water Pollution

Wastewater – water that flows down the drain

Treatment plants remove most but industrial wastewater and toxic substances are harder to get rid of

Creates sludge – solid material that remains after treatment May contain hazardous materials Incinerated or buried in a landfill

Wastewater Treatment Plants