Water Pollution Types of Water Pollution
Point sources Water Do (ppm) at 20˚C Quality Good Nonpoint sources 8-9 Slightly polluted 6.7-8 Biological oxygen demand Moderately polluted 4.5-6.7 Heavily Water quality polluted Below 4.5 Gravely polluted Below 4 Point and Nonpoint Sources
NONPOINT SOURCES
Rural homes
Urban streets Cropland Animal feedlot
Suburban POINT SOURCES development Factory
Wastewater treatment plant Water pollution Sources
Bacteria,Viruses,Protozoa, Parasitic worms
Oxygen demanding substances Inorganic plant nutrients
Organic chemicals
Sediment or suspended matter
Thermal pollution
Genetic pollution Biological Magnification
Water 0.000002 ppm
Herring gull 124 ppm Phytoplankton 0.0025 ppm
Herring gull eggs 124 ppm
Zooplankton Lake trout 0.123 ppm 4.83 ppm
Rainbow smelt 1.04 ppm Pollution of Streams
Oxygen Sag curve
Pollution of Lakes
Discharge of untreated municipal sewage Nitrogen compounds (nitrates and phosphates) produced by cars and factories (Eutrophication diagram )
Natural runoff Discharge of (nitrates and detergents phosphates ( phosphates)
Manure runoff From feedlots (nitrates and Discharge of treated Phosphates, municipal sewage ammonia) (primary and secondary treatment: nitrates and phosphates) Runoff from streets, lawns, and construction Lake ecosystem lots (nitrates and nutrient overload phosphates) and breakdown of chemical cycling Runoff and erosion Dissolving of (from from cultivation, nitrogen oxides mining, construction, (from internal combustion and poor land use) engines and furnaces) Fig .22.7, p. 499 Groundwater Pollution: Causes
Hazardous waste injection well Pesticides Coal strip De-icing mine runoff Buried gasoline road salt and solvent tank Pumping Cesspool well Gasoline septic tank station Waste lagoon Water pumping Sewer well Landfill Accidental Leakage from faulty spills casing Discharge
Confined aquifer
Groundwater flow Leaking tank
Water table
Groundwater flow Free gasoline Gasoline dissolves in leakage plume groundwater (liquid phase) (dissolved Migrating phase) vapor phase Contaminant plume moves Water well with the groundwater Global Outlook: Stream Pollution in Developing Countries
Water in many of central China's rivers are greenish black from uncontrolled pollution by thousands of factories.
Figure 20-7 Case Study: India’s Ganges River: Religion, Poverty, and Health
Religious beliefs, cultural traditions, poverty, and a large population interact to cause severe pollution of the Ganges River in India. Very little of the sewage is treated. Hindu believe in cremating the dead to free the soul and throwing the ashes in the holy Ganges. Some are too poor to afford the wood to fully cremate. Decomposing bodies promote disease and depletes DO. Case Study: India’s Ganges River: Religion, Poverty, and Health
Daily, more than 1 million Hindus in India bathe, drink from, or carry out religious ceremonies in the highly polluted Ganges River. Water Pollution Prevention
Monitoring aquifers
Strictly regulating hazardous waste disposal Storing hazardous materials above ground Reducing Water Pollution through Sewage Treatment
Primary and Secondary sewage treatment. Technological Approach: Using Wetlands to Treat Sewage
(
Sewage Treated water Wetland type Wetland type plants plants
45 centimeter layer of limestone gravel coated with First concrete pool decomposing bacteria Second concrete pool
( Drinking Water Quality
Bottled water
Safe Drinking Water Act
Maximum contaminant levels Is Bottled Water the Answer?
Some bottled water is not as pure as tap water and costs much more. 1.4 million metric tons of plastic bottles are thrown away. Fossil fuels are used to make plastic bottles. The oil used to produce plastic bottles in the U.S. each year would fuel 100,000 cars. Using Laws to Protect Drinking Water
The U.N. estimates that 5.6 million Americans drink water that does not meet EPA standards. 1 in 5 Americans drinks water from a treatment plant that violated one or more safety standard. What Can You Do? Water Pollution
• Fertilize garden and yard plants with manure or compost instead of commercial inorganic fertilizer.
• Minimize your use of pesticides. • Do not apply fertilizer or pesticides near a body of water. • Grow or buy organic foods.
• Do not drink bottled water unless tests show that your tap water is contaminated. Merely refill and reuse plastic bottles with tap water.
• Compost your food wastes.
• Do not use water fresheners in toilets.
• Do not flush unwanted medicines down the toilet.
• Do not pour pesticides, paints, solvents, oil, antifreeze, or other products containing harmful chemicals down the drain or onto the ground. Roger Rosenblatt
It is a hard truth to swallow, but nature does not care if we live or die. We cannot survive without the oceans, for example, but they can do just fine without us.