Water Pollution Chapter 11 Section Three The water you pollute may be your own!

What is water pollution and where does it come from? The introduction of chemical, physical, or biological agents into water. Point source – discharged from a single source, such as a factory or mine Non-point – from many different sources, hard to identify, cause of 96% of polluted water in United States

Principal water pollutants PollutantSource Pathogens-nonpoint, sewage, animal waste Organic matter-mostly nonpoint sources Organic chemicals- nonpoint, farms, lawns, underground storage tanks Inorganic chem- both, industial waste, roads, waste water, acid rain Heavy metals- both, mining, industry, chemicals, landfills Physical agents-both, heat, suspended solids

Wastewater treatment Wastewater – water that contains waste from home or industry Sewage sludge – solid waste product of wastewater treatment, may be toxic, used as fertilizer if not toxic

Wastewater Treatment Process

Eutrophication Too many nutrients cause excess growth of plants and algae. When they die, bacteria that breakdown dead plants uses oxygen. No oxygen – fish die! Artificial eutrophication – caused by humans, too much fertilizer, on farms, yards, gardens.

Misc. Pollutants Thermal – water temp. is too high, from power plants and industry, kills fish due to oxygen content of water. Groundwater – polluted surface water percolates down, causes: leaking storage tanks, pesticides, oil, fertilizer.

Major sources of groundwater pollution

Ocean Pollution 85% comes from land activities Cruise ships dump 15 billion pounds/year Oil spills – 37 million gallons/year from tanker accidents Nonpoint land sources add 200 – 300 million gallons/year

Pollution and Ecosystems Causes immediate damage to ecosystems Biomagnification – accumulation of pollutants at successive levels in the food chain Cleaning Up – Clean Water Act of 1972 was first major legislation to improve water quality