AP Environmental Science Mr. Grant Lesson 73 APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment AP Environmental Science Mr. Grant Lesson 73 Fresh Water Pollution and Its Control & Wastewater and Its Treatment

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Objectives: Define the terms point-source pollution and non-point- source pollution. Assess problems of water quality and propose solutions to address water pollution. Explain how we treat drinking water and wastewater. TED - Too much of the world lacks access to clean drinking water. Engineer Michael Pritchard did something about it -- inventing the portable Lifesaver filter, which can make the most revolting water drinkable in seconds. An amazing demo from TEDGlobal 2009.

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Define the terms point-source pollution and non-point-source pollution. Point-Source Pollution: Non-Point-Source Pollution: Point-Source Pollution: A source of pollution that involves the discharge of wastes from an identifiable point, such as a smokestack or sewage treatment plant. Non-Point-Source Pollution: A source of pollution that cannot always be traced to an exact point of entry.

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Assess problems of water quality and propose solutions to address water pollution. Water pollution stems from point sources and nonpoint sources. Water pollutants include toxic chemicals, sediment, thermal pollution, excessive nutrients, and microbial pathogens, Scientists who monitor water quality use biological, chemical, and physical indicators. Groundwater pollution can be more persistent and difficult to address than surface water pollution. Preventing water pollution is better than mitigation. Legislation and regulation have improved water quality in developed nations in recent decades.

Freshwater pollution and its control APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Freshwater pollution and its control Water for human consumption and other organisms needs to be: Disease-free Nontoxic Half of the world’s major rivers are seriously depleted and polluted They poison surrounding ecosystems Threatening the health and livelihood of people The invisible pollution of groundwater has been called a “covert crisis”

Point and nonpoint sources of pollution APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Point and nonpoint sources of pollution Pollution = the release of matter or energy that causes undesirable impacts on the health and well-being of humans or other organisms **Point sources = discrete locations of water pollution Factories, sewer pipes** Addressed by the U.S. Clean Water Act Nonpoint sources = pollution arises from multiple inputs over larger areas (farms, city streets, neighborhoods) The major source of U.S. water pollution

Freshwater pollution sources APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Freshwater pollution sources

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Nutrient pollution Nutrient pollution from fertilizers, farms, sewage, lawns, golf courses leads to eutrophication Fertilizers add phosphorus to water, which boosts algal and aquatic plant growth Spreading algae cover the surface, decreasing sunlight Bacteria eat dead algae, reducing dissolved oxygen Fish and shellfish die Solutions include treating wastewater Reducing fertilizer application Using phosphate-free detergents Planting vegetation to increase nutrient uptake The Dümmer See, a lake in Germany's Lower Saxony, suffers from heavy nutrient pollution.

Eutrophication is a natural process, but… APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Eutrophication is a natural process, but… Human activities dramatically increase the rate at which it occurs

Pathogens and waterborne diseases APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Pathogens and waterborne diseases Enter water supplies through inadequately treated human waste and animal waste from feedlots Fecal coliform bacteria indicate fecal contamination They are not pathogenic organisms But the water may also hold other disease-causing pathogens (e.g., giardiasis, typhoid, hepatitis A) **Bacterial (i.e., pathogens) pollution causes more human health problems than any other type of water pollution** Conditions are improving 86% of people now have safe water

Pathogens cause human health problems APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Pathogens cause human health problems 1 billion are still without safe water 2.6 billion have inadequate sewer or sanitary facilities Mostly rural Asians and Africans Health impacts kill 5 million people per year Solutions: Disinfect drinking water Treat sewage Public education to encourage personal hygiene Government enforcement of regulations protecting food Pathogens that can be spread through drinking water

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Toxic chemicals Pesticides, petroleum products, synthetic chemicals Arsenic, lead, mercury, acid rain, acid drainage from mines Effects include poisoned animals and plants, altered aquatic ecosystems, and decreased human health Solutions: Issue and enforce more stringent regulations of industry Modify industrial processes Modify our purchasing decisions Many of these chemicals are potentially harmful and can spawn health problems.

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Sediment pollution Sediment in rivers can impair aquatic ecosystems Clear-cutting, mining, clearing land for housing, and cultivating farm fields expose soil to erosion It dramatically changes aquatic habitats Fish may not survive Solutions: Better management of farms and forests Avoid large-scale disturbance of vegetation

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Thermal pollution Water that is too warm causes problems Warmer water holds less oxygen Dissolved oxygen decreases as temperature increases Industrial cooling heats water Removing streamside cover raises water temperature Water that is too cold also causes problems Water at the bottom of reservoirs behind dams is colder When water is released, downstream water temperatures drop suddenly, killing aquatic organisms

Indicators of water quality APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Indicators of water quality Scientists measure properties of water to characterize its quality Biological indicators: presence of fecal coliform bacteria, disease-causing organisms, algae, etc. Chemical indicators: nutrient concentrations, pH, taste, odor, hardness, dissolved oxygen Physical indicators: color, temperature, turbidity

Groundwater pollution is a difficult problem APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Groundwater pollution is a difficult problem Groundwater is increasingly contaminated But is hidden from view and difficult to monitor “Out of sight, out of mind” Groundwater pollution is hard to address It retains contaminants for decades and longer It takes longer for contaminants to break down because of lower sunlight, microbes, and dissolved oxygen So far, the EPA has cleaned up 388,000 leaking tanks

Sources of groundwater pollution APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Sources of groundwater pollution Some toxic chemicals occur naturally Aluminum, fluoride, sulfates Pollution from human causes wastes leach through soils Pathogens enter through improperly designed wells Leaking underground storage and septic tanks

Agriculture and industry pollute groundwater APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Agriculture and industry pollute groundwater Agricultural pollution comes from several sources Pesticides are in most of the shallow aquifers tested Nitrates from fertilizers have caused cancer, miscarriages, and “blue-baby” syndrome Pathogens like Escherichia coli (E. coli) Manufacturing industries and military sites have been heavy polluters By-products seep into water from miles around Radioactive wastes will contaminate water for 750,000 years

It is best to prevent pollution APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment It is best to prevent pollution It is far better to prevent pollution than use “end-of-pipe” treatment and cleanup Other options are not as good: Removing just one herbicide from water in the U.S. Midwest costs $400 million/year Pumping, treating, and re-injecting it takes too long Consumers can purchase sustainably made products Become involved in local “riverwatch” projects Urge government to pursue policies to fight pollution

Legislative efforts reduce pollution APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Legislative efforts reduce pollution Water pollution was worse decades ago Citizen activism and government response resulted in legislation during the 1960s and 1970s The situation is much better now The Federal Water Pollution Control Act (1972) Renamed the Clean Water Act in 1977 It is illegal to discharge pollution without a permit Sets standards for industrial wastewater Funded sewage treatment plants

Enforcement of water quality is decreasing APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Enforcement of water quality is decreasing Underfunded and understaffed state and federal regulatory agencies were pressured by industries and politicians Violations of the Clean Water Act have risen to over 100,000 documented violations/year 10% of Americans are unknowingly exposed to unsafe drinking water The new EPA administrator has promised to improve Citizens pushed politicians to improve the Great Lakes The water quality of the lakes has dramatically improved Chart comparing Virginia's population growth to its CZMA funding level.

Explain how we treat drinking water and wastewater. APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Explain how we treat drinking water and wastewater. Municipalities treat drinking water by filtering and disinfection in a multistep process. Septic systems are used to treat wastewater in rural areas. Wastewater is treated physically, biologically, and chemically in a series of steps at municipal wastewater treatment facilities. Artificial wetlands enhance wastewater treatment while restoring habitat for wildlife.

We treat our drinking water APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment We treat our drinking water Technology and government regulation have improved our pollution control Treated drinking water is widespread and successful in developed nations Before water reaches the user, it is chemically treated, filtered, and disinfected The EPA sets standards for over 90 drinking water contaminants Local governments and private water suppliers must meet these standards

We treat our wastewater APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment We treat our wastewater Wastewater = water people have used in some way Household, manufacturing, stormwater runoff, etc. It is treated before being released into the environment Septic systems = the most popular method of wastewater disposal in rural areas Underground septic tanks separate solids and oils from wastewater The water drains into a drain field, where microbes decompose the pollutants Solid waste is periodically pumped out and landfilled

Municipal sewer systems APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Municipal sewer systems In populated areas, sewer systems carry wastewater to treatment locations **Step one… physically screen water to remove large debris** Primary treatment = physically removes contaminants in settling tanks (clarifiers) Secondary treatment = water is stirred and aerated Aerobic bacteria degrade organic pollutants Water treated with chlorine (and/or ultraviolet light) is piped into rivers or the ocean Reclaimed water is used for lawns, irrigation, or industry

A typical wastewater treatment facility APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment A typical wastewater treatment facility Sludge = solid material resulting from treatment Is decomposed microbially Then landfilled, incinerated, or used as fertilizer on cropland Methane-rich gas created by decomposition can be burned to generate electricity

Artificial wetlands clean wastewater APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment Artificial wetlands clean wastewater After primary treatment at a conventional facility Water is pumped into the wetland Microbes decompose the remaining pollutants **Cleansed water is released into waterways** Or percolates underground They are havens for wildlife and areas for human recreation The U.S. has over 500 artificially constructed or restored wetlands

APES Lesson 73 - Fresh Water Polution and its Control & Wastewater and its Treatment TED Video With cutting-edge nanotech, Michael Pritchard's Lifesaver water-purification bottle could revolutionize water-delivery systems in disaster-stricken areas around the globe. "On the outside, it looks like an ordinary sports bottle. On the inside, there's a miracle: an extremely advanced filtration system that makes murky water filled with deadly viruses and bacteria completely clean in just seconds." Allison Barrie, FoxNews.com Michael Pritchard's water filter turns filthy water drinkable (9:29)