Water Pollution Any physical, chemical, or biological change in water quality that has a harmful effect on living organisms or that makes water unusable for desired uses.

Classes of water pollutants 1. Disease-causing agents 2. Oxygen demanding wastes 3. Water-soluble inorganic chemicals 4. Inorganic plant nutrients 5. Organic chemicals 6. Sediments/suspended matter 7. Water-soluble radioactive isotopes 8. Thermal pollution

Pathogens Coliform bacteria (fecal coliforms) Standard drinking = 0 in 100mL Standard swimming = 200 in 100mL

Oxygen demanding wastes Organic wastes that can be decomposed by aerobic bacteria Measurement of oxygen required by bacteria is called BOD = biological oxygen demand

Water-soluble inorganic chemicals Acids, salts, toxic metals (mercury & lead)

Inorganic plant nutrients (fertilizers) Water-soluble nitrates and phosphates –Result indirectly in depleted oxygen –Consumption can lower oxygen carrying capacity of the blood

Organic chemicals (carbon chemistry) Oil, gasoline, plastics, pesticides, cleaning agents, detergents, solvents and others

Silt, sediment, suspended matter Insoluble particles of soil and other Cause cloudiness in water –Reduces photosynthesis –buries fish eggs –clogs gills Silting also fills channels, harbors, and reservoirs Measurement is called turbidity

Radioactive Isotopes

Oyster Creek Nuclear Plant

Thermal pollution Cool water is drawn in by industrial plants, used to cool machinery, and returned to river at warmer temperature This warmer water lowers D.O. Fish can suffer thermal shock

Detecting water pollution 1. Water quality tests 2. Indicator species

Classifying sources of water pollution Two types: point and non-point Point source = pipes, sewers, ditches

Non-point = runoff from watershed EPA estimates that 33% of all contamination in lake and estuaries is caused by runoff

Pollution in streams Moving waters allow streams to recover more quickly than lakes Biodegradable wastes are broken down more quickly in streams and rivers than in lakes

Lake Pollution Less mixing in lakes This makes lakes more vulnerable to pollution Fish can’t escape pollutants

Cultural Eutrophication Aerobic bacteria that break down algae use up oxygen Algae & duckweed grow in population explosion Fertilizers, animal wastes, Run into lake Algal bloom Which leads to …………

……. a “fish kill”

Prevention Advanced waster water treatment Bans or limits on phosphates in detergents Soil conservation and land-use to reduce runoff

Cleanup Dredging Removal of excess weeds

Noteworthy cases The Great Lakes-pollution(point/non-point) The Hudson River-PCBs Chesapeake Bay-pollution(point/non-p) Colorado River-water rights Hetch Hetchy Valley-to dam or undam James Bay, Canada-water diversion Mono Lake-water diversion, overuse Aswan Dam

Ocean Pollution “The ocean is the ultimate sink”

We live on coasts

Most affected Coastal areas Estuaries, wetlands, reefs, swamps ½ of world population lives within 150 miles of coast Bangladesh, Malaysia, Philippines, Thailand, Indonesia Mediterranean Sea 85% untreated

U.S. 35% of raw sewage goes untreated Santa Monica Chesapeake Bay –Drains six states –Only 1% of runoff goes out to ocean

Ocean Pollutants Dredge spoils –From harbor dredging Sewage sludge –From wastewater and sewage treatment plants –US banned in 1992 –London Dumping Convention of 1972, 1983, 1994 Oil (equal to more than 1,000 Exxon Valdez)

Protecting the Coasts Prevention –Separate pipes –Discourage dumping –Protect sensitive and ecologically valuable areas –Use eco land-use planning –Double hulls on ships –Recycle oil Cleanup –Improve cleanup technologies –Require secondary treatment of coastal sewage

Clean Water Act (CWA) 1972 Clean Water Act! Main goal was to make all surface water safe for swimming and fishing by 1983

Clean Water Act Was first called Water Pollution Control Act, was amended to the Clean Water Act 1987 Water Quality Act Main goal was to make all surface water safe for swimming and fishing by 1983

More CWA Also sought to restore chemical integrity of the water Some gains have been made over point source pollution Little gains made in non point source 1995 established discharges trading policy

And still more laws… Source Water Assessment Program (SWAP), 1996 SWPP, 1996 Surface Water Treatment Rule, 1996

Clean Water Act Results Some gains have been made over point source pollution few gains made in non point source

Results of CWA! % % % of US lakes And rivers That are fishable and swimmable

Results of CWA phosphorus DDT

Laws, Treaties, Legislation Safe Drinking Water Act, 1974 Water Quality Act, 1965 Clean Water Act, 1972

More Laws Emergency Wetlands Resources Act, 1986 Soil and Water Conservation Act, 1977 Wild and Scenic Rivers Act, 1968 Marine Plastic Pollution Research and Control Act, 1987 Ocean Dumping Ban Act, 1988 Oil Spill Prevention and Liability Act, 1990 Water Resources Development Act, 1974 National Estuary Program (NEP), 1987