190 likes | 324 Views
Chapter 15: Freshwater Pollution and Its Control. Kristen Sturdivan Hailee Maas Olivia Abbott Megan Miller. Water pollution takes many forms. Over half the world’s major rivers are seriously depleted and polluted.
E N D
Chapter 15: Freshwater Pollution and Its Control Kristen Sturdivan Hailee Maas Olivia Abbott Megan Miller
Water pollution takes many forms • Over half the world’s major rivers are seriously depleted and polluted. • Pollution: release of matter/energy into the environment that cause undesirable impacts on health of humans/organisms (can be physical, chemical, or biological) • Nutrient Pollution: excess phosphorus boosts growth caused by runoff from farms, golf courses, lawns, ad sewage • Reduce by purchasing phosphate-free detergents and reduce fertilizers and planting specific vegetation
Water pollution takes many forms (cont.) • Pathogens and waterborne diseases: can enter drinking water supplies via human/animal waste • 82% population has access to safe water • 1.1 billion without safe water supplies • 2.4 billion no sewer/sanitation facilities • 4/5 lived in rural areas
Water pollution takes many forms (cont.) • Toxic Chemicals: pesticides, petroleum products, and other synthetic chemicals • Acid rain • Acid drainage • Cause cancer • Poison animals and plants • Alter aquatic ecosystems • Sediment: rivers transport sediment from farmland, mining, clear-cutting, and land clearing for housing development to different areas through rivers and floods. • When a clear-water river receives a heavy influx of eroded sediment , aquatic habitats can change dramatically
Water pollution takes many forms (cont.) • Thermal Pollution: raised by the use of water to cool an industrial facility and putting it back in the river and removing streamside vegetation that shades water. • When temperature rises the water’s ability to hold dissolved oxygen decreases! Too little heat can also case problems: • These rivers that have dams (Colorado) and colder temperatures favor a cold-loving invasive trout species over the native suckerfish.
Water pollution comes from point and non-point sources • Point Sources: discrete locations such as a factory or sewer pipe • Non-Point Sources: multiple cumulative inputs over larger areas such as farms, city streets, and residential neighborhoods • US Clean Water Act: targeted industrial discharges and addressed point-source pollution • Non-Point source pollution still exerts a greater impact on water quality in he US today!
Scientists use several indicators of water quality • Forms of water pollution • 1. Physical • 2. Chemical • 3. Biological • Scientists and technicians measure the properties of water to characterize its quality.
Biological Include the presence of fecal coliform bacteria and other disease causing organisms Algae and aquatic invertebrates are used as biological indicators of water quality
Chemical • Includes nutrient concentrations, pH, taste ad ordor, and hardness • Hard water contains high concentration of calcium and magnesium ions. • Dissolved oxygen is an indicator of aquatic ecosystem health • Surface water low in dissolved oxygen are less capable of supporting aquatic life
Physical • Turbidity measures the density of suspended particles in a water sample • EX: Colorado River • Good indicator of overall water quality • Water color can reveal particular substances in a sample • Tannins- decomposing leaf litter • Temperature is used to access water quality • Warmer water holds less dissolved oxygen
Groundwater pollution is a serious problem • Groundwater pollution is mainly caused by agriculture and industrial practices • Hidden from view • Hard to monitor • Out of mind until widespread contamination of drinking supplies is contaminated • Groundwater pollution retains its contaminants until they decompose • DDT- found widely in U.S. aquifers even though it was banned 35 years ago
Decomposition of Groundwater • Groundwater contains less dissolves oxygen, micro tubes, minerals, and organic matter • Decomposition is slower • Concentrations of the herbicide alachlor decline by half after 20 days in soil, but in groundwater this takes almost 4 years
There are many sources of groundwater pollution • Many ground water chemicals can become toxic at certain doses: Aluminum, Fluoride, Nitrates, & Sulfates. • Bangladesh’s wells. • Industrial, agricultural, and urban wastes – from heavy metals to petroleum products to industrial solvents to pesticides- leach through the soil into aquifers. • Volatile Organic Compounds (VOCs) were sampled and found in most aquifers and 20% of industrial wells in 2006. • Leakage from underground septic tanks, tanks of industrial chemicals, and tanks of oil and gas pollute ground water • EPA work in 2007- confirmed leaks on 468,000 tanks, initiated clean up on 439,000 tanks, and completed clean ups on 357,000 tanks. • Once an aquifer is contaminated it is extremely hard to remediate.
There are many sources of groundwater pollution • Agriculture can pollute the groundwater too: • Pesticides were detected in over half of the shallow aquifer sites in the US- mid 1990s. • Nitrate from fertilizers leech into ground water. • Nitrates in drinking water has been linked to cancer, miscarriages, and “blue baby” syndrome. • Pathogens in the water; Walkerton, ON in 2000 was contaminated with E Coli – 2,000 became ill and 7 died. • Manufacturing and military sites have been heavy polluters. • WW2 TNT producers caused Nitro aromatic by products to seep into the ground water for miles around • Cleanup started with the 1980 Superfund legislation. • The Superfund also helped clean up the Hanford Nuclear Reservation in WA state – nuclear waste site with a half life of a quarter million years.
Legislative and regulatory efforts have helped reduce pollution • Many ground water chemicals can become toxic at certain doses: Aluminum, Fluoride, Nitrates, & Sulfates. • Bangladesh’s wells. • Industrial, agricultural, and urban wastes – from heavy metals to petroleum products to industrial solvents to pesticides- leach through the soil into aquifers. • Volatile Organic Compounds (VOCs) were sampled and found in most aquifers and 20% of industrial wells in 2006. • Leakage from underground septic tanks, tanks of industrial chemicals, and tanks of oil and gas pollute ground water • EPA work in 2007- confirmed leaks on 468,000 tanks, initiated clean up on 439,000 tanks, and completed clean ups on 357,000 tanks. • Once an aquifer is contaminated it is extremely hard to remediate.
We treat our drinking water Technological advancements allows us to treat drinking water and waste water. The EPA ensures standards are set for over 80 drinking water containments Water from an aquifer is treated with chemicals to remove particular matter These matters can be passed through filters of sand, gravel, and charcoal
It is better to prevent pollution than to mitigate it after it occurs Filtering groundwater before distributing it can be expensive ($400 million annually) Pumping water, treating it, and then injecting the water back in, takes a lot of time after a while Also the clean up bill has been know to be around 1 trillion Restricting pollutants elsewhere usually just means that those pollutants will end up some place else.
Some Things That Work You can buy phosphorus-free detergents, or “environmental friendly” products You can become involved in protecting lacal waterways
Wastewater and its Treatment Wastewater *refers to water that has been by people in some way* Examples – water carrying sewage; water from showers, sinks, washing machines, and dishwashers; also water used in manufacturing or cleaning processes by businesses and industries; and storm water runoff. A large amount of waste water can harm ecosystems and pose treats to the human health