Chapter 18 Water Pollution

18.1 Water Pollution

• Water pollution is anything that degrades water quality– Chemical– Biological– Particulate Matter– Taste– Esthetics– Thermal

18.2 Types And Effects Of Water Pollutants

• Infectious agents remain an important threat to human health

• Bacteria are detected by measuring oxygen levels • Coliform Bacteria– Not Dangerous, but Indicate Fecal Contamination

• Nutrient enrichment leads to cultural eutrophication – BOD = Biological Oxygen Demand

• Eutrophication can cause toxic tides and “dead zones”

18.2 Types And Effects Of Water Pollutants

• Inorganic pollutants include metals, salts, acids, and bases (alkalis)

• Organic pollutants include drugs, pesticides, and other industrial substances

• Sediment also degrades water quality • Thermal pollution is dangerous for organisms

18.3 Water Quality Today • The Clean Water Act protects our water • The importance of a single word • Water quality problems remain • Other countries also have serious water

pollution • Groundwater is hard to monitor and clean • There are few controls on ocean pollution– London Dumping Convention 1990

18.4 Water Pollution Control

• Source reduction is often the cheapest and best way to reduce pollution

• Controlling nonpoint sources requires land management

• Human waste disposal occurs naturally when concentrations are low

• Water remediation may involve containment, extraction, or phytoremediation

18.5 Water Legislation• The Clean Water Act of 1972 was ambitious,

bipartisan, and largely successful – “Fishable and Swimmable”

• What Can You Do? Steps You Can Take to Improve Water Quality – Don’t Dump Pollutants (Lawn Fertilizer, Motor Oil, Pet

Waste)• Clean water reauthorization remains contentious – Unfunded Mandates

• Other important legislation also protects water quality