Water Quality Think for a few moments about each question. Try to answer them into your notes. What is water quality? Are all sources of water affected? How do the pollutants get there? What are some key pollutants?

Water Quality Physical, chemical, biological characteristics. Concerns for drinking water, human safety, and ecosystem health. Use scientific standards to test. Water sources affected: Most often surface water Ground water is more difficult to detect

Sources of Pollution Industrial pollution is a major cause Runoff from agricultural areas Urban storm water runoff Discharge of untreated sewage (especially in developing countries.)

Point Source Pollution Comes from one specific location

Examples: Overflows of sanitary sewers Overflows of animal agriculture waste storage Illegal dumping Oil spills from barges in the ocean Smoke stacks from factories

Non-Point Source No specific dumping site Runoff, leaky pipes (septic tanks), landfills, pollutants trapped in the water cycle are carried long distances.

Sources of Water Pollution Clean Water Act protects against both Point Source Non-Point Source Similarities Wide, diffuse, difficult to ID source of pollution Identifiable, localized entry point of pollution Clean Water Act protects against both Cleanup is easier, depending on pollutant Cleanup is very difficult of diffuse pollutants Harmful to drinking water, wildlife, fisheries, recreation Ex: Runoff or snowmelt of oil or pesticide Ex: Oil Spill or Factory Smokestack

Eutrophication Excess nutrients in the water cause explosive plant growth When many plants die, they produce a toxin (red algae) Decaying plants also reduce the amount of oxygen in the water Plant growth (like algae) can suffocate other life in a lake or pond.

Gulf of Mexico

Solutions to the Problem Clean Water Act Desalination

Clean Water Act Came about in 1972 when a river in Ohio was so polluted that it caught on fire and burned for several days Goal was to make all surface water clean enough for fishing and swimming by 1983 Goal was not achieved, but lakes and rivers that are clean have increased by 30% and toxic metals are now removed from wastewater

Desalination Water comes from the ocean Can use desalination to remove the salt from the salt water to have fresh water Heat the salt water and collect the fresh water that evaporates However, the process is very expensive and also requires lots of energy

Waterborne Disease Number one killer of children worldwide About 80% of all diseases are water-related (WHO) Often due to water infiltrated with sewage, spreading disease Bacteria, virus, or protozoa are resposible – can’t be seen, smelled, or tasted and can be in “clean looking” water Improvements in disposal and treatment have reduced number of illness in developed nations

San Diego, CA 11/30/08 This woman is drinking from a “Life Straw” –said to filter particles and bacteria from water.

http://www.cdc.gov/Mmwr/preview/mmwrhtml/figures/s904a1f2.gif

But It’s Just a Bottle of Water Read through the text. UNDERLINE all important information. Answer the questions in complete sentences on a separate sheet of paper. Turn in by the END OF CLASS to receive full points. Work turned in after the break will have an automatic 20 points taken off!