Wastewater treatment and water recycling
Why care- we depend on for survival. Largely needed to produce food. (example: it takes about 40 gallons ( 1 full bathtub) to produce 1 cup of coffee)). Water plays a key role in controlling the climate. Earth has an abundant and renewable supply of water, yet it is unevenly distributed.
Quick need to know- water’s high boiling point is due to the unusual forces of attraction of its molecules. Heat converts liquid water into water vapour and cooling of the water vapour bring it back to its liquid state. This store and release heat ability help distribute the sun’s heat throughout the atmosphere and around the globe. Unlike most liquids, water expands when frozen. Thus ice floats. Water cycle- purifies and distributes the earth’s fixed supply of water within the environment and the earth’s life-support systems, through evaporation, transpiration and precipitation. Most water either becomes surface water through surface runoff or becomes groundwater stored in aquifers.
**pretend the global water supply was a 40 gallon( 5,120 fluid ounces) bathtub. Then the fresh water available to us would be a shot glass or 1.2 fluid ounces.**30% of the 0.024% of earth’s freshwater is stored in aquifers. These aquifers are deep underground, thus they are recharged, if any, very slowly.
Problems- up to 70% of reliable runoff is used for irrigation. It is projected that we may be drawing as much as 90% by 2025 dams provide water to thousands of people yet they cause about one-fifth of the world’s freshwater plant and fish species to become endangered/ extinct. Dams displace people to make the dam. Some 40 to 80 million people have been displaced from their homes by dam-and-reservoir projects. Groundwater is being overpumped because, on average, groundwater is used four times faster to irrigate crops, then it is being replenished. ** because acquires recharge slowly, once depleted they may be efficiently gone forever. Depleted aquifers can disrupt agricultural systems, natural ecosystems, many wetlands, lakes and rivers. Many plants and animals in the area of the depleted aquifer may migrate. At times taking large amounts of groundwater causes the porous rock in the aquifer to collapse. This results in the land above the aquifer to sink. Water transfer systems are a good idea, however, most of the water is used to irrigate crops in desert-like climates, which in turn makes the whole process pointless. According to WHO ( world health org) about 2 million people, more than 80% of them children under 5 years old, die from diseases caused by drinking contaminated water. since 1990, 2.4 billion people have gained access to safe drinking water supplies. However, some experts warn that projected climate disruptions in many parts of the world could reverse these positive trends. The removal of forest, wetlands rid places where flooding is common of its protection. Deforestation exposes forest soils to erosion. Flooding washes these soils into bodies of water, which can smother aquatic systems and contaminate drinking water.
What can be done- Firstly we can try to draw more water or move more water. Which will have minimal success because there is a fixed number of water. Pros and cons of dam: provide water for irrigation, drinking and other uses. Produce electricity. Can control flooding. Cons- reservoirs flood forest and cropland and displace people. Can disrupt aquatic ecosystems. Pros and cons of pumping more groundwater: Groundwater is found almost everywhere. It is available year-round in most cases and is renewable if not over pumped. Cons- aquifer depletion from overpumping, which leads to land subsidence. Saltwater intrusion into coastal freshwater aquifers. Pros and cons of water transfer projects: supply irrigation water to produce more food. Provide water supplies for urban areas and industry as well as, support and expand aquatic ecosystems. Cons- discourages water conservation because water prices are low. May harm people and economies in areas where the water is withdrawn. Also may disrupt aquatic systems where the water is being withdrawn. Currently desating sea water meets less the 1% of the worlds demand and only about 0.4% of the U.S. demand for freshwater. Many water resource experts say that the first step serious step to conserve water would be to make it more expensive. Ex. when governments provide farmers with cheap irrigation water. Note. each household would receive enough water for basic needs but if they want more than they need to pay higher prices. Increase in irrigation efficiency. About 60% of irrigated water does not go to the crops. There are better technologies to irrigate water. Where about 90% of the water used goes to the crops. In order for us to reduce our contribution to the coastal flooding, we must cut our emissions for carbon dioxide and other greenhouse gases dramatically and stop massive deforestation.
What you can do- Use water wisely. Showering instead of taking a bath can cut bathing water use by two-thirds. Washing only full loads of dishes in dishwashers and clothing in clothes washers cuts the number of loads and the amount of water required. Water gardens and lawns at night or in the early morning can greatly reduce water losses from evaporation.
An example of the ground sinking due to an aquifer being depleted:
Why care- your life process depends on water. Water pollution is any physical or chemical change in surface water or groundwater that can harm living organisms. Every year thousands of people become sick due to drinking polluted water. Aquatic ecosystems are threatened by water pollution. Some cases of water pollution results n ecosystems collapse. Polluted water can make us sick or kill us, and it can disrupt aquatic ecosystems.
Problems- humans take water from river, aquifers and lakes faster then it can be replenished. We rid the land of its trees in order to farm, mine, build roads, or to expand cities. Precipitation runs off of these artificial surfaces, thus water cannot trickle down the earth: replenishing aquifers. Artificial buildings contribute to flooding because of water going to the streams over aquifers. When we drain wetlands and fill them for farming we are disrupting earth natural sponges. Wetlands absorb precipitation and hold it which helps recharge aquifers. Factories and sewage treatment plants that fair to remove all pollutants for wastewater are prime examples of point source pollution. Sediment eroding from farms is the largest form of nonpoint-source water pollution. Mining leaves large piles of rubble which are a major source of eroded sediments and toxic chemicals that may seep into groundwater. Half of the world’s rivers are heavily polluted. Most of these polluted streams run through less developed countries. The majority of this pollution is from untreated sewage and industrial waste. 4 out of 10 people in the world live on or near a seacoast. The coastal population is slowly rising. According to a 2006 UN Environmental programme report: 80-90% of sewage from cities living on the coast in less developed countries was dumped into oceans untreated. Untreated sewage release chemicals that lead to algae blooms. These harmful blooms release toxins that poison fish and kill other animals such as fish-eating birds and pet dogs. These blooms often result in the closing of recreational beach areas. Every year harmful algal bloom leads to the posing of about 60 thousand Americans who eat contaminated shellfish on average. These bloom result in oxygen-depleted zones, where the fish have died off due to lack of oxygen. After the oxygen-consuming organisms die off the zone is called a dead zone. In the form of fertilizers, pesticides, gasoline, motor oil, paint thinners and other toxic chemicals, pollutants seep into the ground thus polluting the groundwater. Ocean Acidification- the process of the ocean water absorbing CO2. which reacts with the water to form a weak acid (Carbonic acid) thus increasing the acidity of the ocean.
What can be done- it is easier, less expensive, to prevent pollution from happening then to clean it up. Ways to control runoff and soil erosion for sloping land is to use a combination of contour planting and strip cropping. For flatland alley cropping may be more effective. We should quickly step up the research on rising ocean acidity. Everyone should take the necessary steps to sharply reduce our CO2 emissions. Which is the root of the problem. Do not dump chemicals or unused medicines down home or municipal drains or into aquatic systems. Prevent yard wastes from entering the stormwater systems in your community. Try to buy only products that were made by companies that do their best to prevent or reduce their own water pollution. Choosing recreational activities that minimize pollution of aquatic systems, such as canoeing and swimming, and avoiding motorized water activities. Fertilizing yards or gardens with manure or compost instead of with commercial fertilizers. Being socially and politically active in helping to prevent pollution. Talking about water pollution problems and solutions with their friends and families. Supporting politicians who give pollution control a high priority.
The plastic in our oceans:
Why care- crop losses, drought and prolonged flooding are effects of climate change that we will see in this century. Al well as species may go extinct in this century
Quick need to know-weather is the temperature in a local area climate is the average temperature for around the globe.
Problems- The increased acidity of the ocean damages coral reefs and certain marine creatures who cannot make their calcium carbonate shells and exoskeletons. As well as acidic oceans make it more difficult for these organisms to replace them. According to Nancy Knowlton, a coral reef biologist, coral reefs will cease to exist as physical structures by 2100 or even 2050. Because shell-building organisms are a critical part of the ocean food web and because a large variety of marine species depend on coral reefs, Ocean acidification is a major threat to all life on earth. The world’s average sea level is most likely to rise 3-6.5 feet this century and to continue rising. The rising is due to atmospheric warming and projected change may threaten at least one-third of the worlds coastal ecosystems, especially coral reefs, which contain most of the worlds aquatic biodiversity, and coastal wetlands that produce much of the worlds seafood and rice. Many people living on coasts will be displaced.
What can be done? Making the places where we live as energy efficient as possible. Insulating ceilings and walls, and sealing all air leaks in our homes. Using energy-efficient windows or clear plastic to cover and seal leaky windows. Use energy-efficient appliances and light bulbs, and insulating electric hot water heaters. Using energy-efficient transportation options like walking, biking, and taking buses or subways whenever possible. When driving is necessary carpool. Driving only energy-efficient vehicles, those that get at least 40 miles per gallon. Making all purchases with climate change in mind. Eating less meat (chicken instead of beef) or no meat, because meat production involves high levels of greenhouse gas emissions. Buying only products that can be reused or recycled, and trying to minimize packaging in all purchases. Buying from companies that are trying to reduce their contributions to climate change. If everyone were to minimize their contributions to climate change, greenhouse gas levels in the atmosphere could be reduced dramatically. In doing this, we would greatly improve our chances of avoiding severe or catastrophic climate disruption.
Areas of Florida (in red) that will be flooded after the ocean levels rise:
Why care- because most waste is casually thrown away or scattered throughout the land as litter, much of the waste ends up in oceans, lakes, and rivers. So much waste has flowed into the oceans that there are now gigantic masses of plastic and other garbage floating around. (it called The Great Pacific Garbage Patch) much of the waste (even buried or burned) still ends up polluting the air, land, soil, and water in which our health and economies depend on. As our waste pile up and pollute our environment, we harm and crowd out earth biodiversity. 80% of the things we throw away are recyclable.
Quick need to know- our economies and lives depend on the energy from the sun, the earth’s natural capital and the recycling of key chemicals required by all life forms. High- consumption, high-waste economies convert much of the high-quality matter and energy resources into waste and pollution. Many economists argue that all economies are human subsystems of earth life-support system because they depend on resources and services provided by the earth.
Problems- Economic systems based on ever-increasing economic growth will likely deplete or degrade much of the earth’s natural assets. So much so that the earth will no longer be able to support these systems. Although the argument for this is that we can find technological solutions, there are no substitutes for vital resources. High-waste economies are exceeding the sustainable capacity the environment has to handle the growing amount of wastes. Market prices do not include hidden costs. Hidden cost includes the cost of harming the environment and human health. For example, the market price we pay for a computer includes the costs of raw materials, labour, marketing, and shipping. However, it does not include harmful environmental and health effects. For instance, the pollutants and wastes that result from the mining of raw materials to make the computer and the ultimate disposal of that computer. The majority of people don’t connect these harmful effects to owning a computer. Yet sooner or later either the computers owner or other people will pay the hidden costs. Whether it’s in the form of higher health-care, poorer health, or higher taxes for pollution control and waste management. Many economists believe that if these costs were included when consumers bought then they would be less willing to buy products that have environmental impacts. As our ecological footprints grow, we are depleting and degrading the earth’s natural assets. 5 planets would be required if everyone on the planet consumed as many resources at the rate of the average American. The united states leads the world in total solid waste produced per person. The USA’s population only counts as 4.6% of the world’s population yet produces 25% of the world’s population. According to the EPA, about 98.5% of this waste is industrial solid waste from mining (76%), agriculture (13%), and industry (9.5%). Many commonly used products contain harmful chemicals. Such as glues, disinfectants, artist paints and inks, and antifreeze. As well as numerous industrial sites contain barrels the leak hazardous wastes. According to a report by a Nevada state agency, spent fuel from a nuclear reactor emits enough radiation to kill a person standing 40 inches away in less than 3 minutes 10 years after it was closed. If all of the world’s nuclear power plants were shut down tomorrow, we would still have to protect ourselves, and many hundreds of future generations of people, from the intensely radioactive solid wastes by using safe storage facilities that do not yet exist. Despite that 80% of electronic waste (e-waste) can be recycled or reused, most e-waste ends up in incinerator or landfills. Most e-waste contains valuable resources, such as high-quality plastics and valuable metals. E-waste is also a source of toxic and hazardous pollutants. The majority of America’s e-waste that is not buried or burned goes to Asia or to poor African Nations to be recycled. However, the environmental regulation are typically weak and labour is cheap in these countries. The workers are exposed to harmful chemicals and many of them are children.
What can be done? Integrated waste management uses a combination of reuse, recycle and composting solid waste and waste management. According to some scientist and economist, we could cut our amount of solid wasted by 75-90% if we made intensive use of integrated waste-management strategies. Reduce involves consuming less, which automatically reduces one’s waste and pollution. This strategy involves asking: Do I really need it or can I get along without it? The important question is typically complicated because most products’ advertising aims to convince us that we need their product. Reuse is where you use a product or material at least twice. For example, we can watch out a travel mug and reuse it every day instead of using one-time plastic or paper ones. Along with reducing our waste it also saves money, because most coffee shops give discounts to people who bring their own mug. Recycling is when discarded solid materials are converted into new material. The EPA estimates that recycling 1 ton of aluminium cans saves energy that is the equivalent of about 1,700 gallons of gasoline. The order of treating hazardous waste is to produce less of it, to reuse or recycle it, or to convert it to less hazardous material, and to safely store the leftovers. Industrial ecosystems are when industrial systems mimic natures ways of dealing with wastes. The best way to deal with e-waste is to prevent it. Most countries have a tax system that is backwards. It discourages the growth of jobs, income and innovation. And encourages the growth of pollution, resource waste and environmental degradation. For example, a better approach would be to lower taxes on labour, income, and wealth, and raise taxes on environmentally harmful activities that produce pollution, wastes, and environmental degradation. However, taxes on environmentally harmful manufacturing processes and goods would have to be phased in over 10–20 years so that businesses can plan for the future. As a result, income, payroll, or other taxes would have to be reduced for balance. Lastly, the poor and lower-middle class would need a safety net in the form of lower prices on essentials until the new pricing system became stabilized. Polls have indicated that once such a tax shift is explained to voters, 70% of people in Europe and the US support it.
Hazardous waste leaking from barrels:
Why care- our steadily increasing use of fossil fuels exposes us to a variety of air pollutants that may cause health problems and death. Many people are exposed to indoor air pollution that’s caused by the burning of wood and charcoal in open fires indoors.
Quick need to know- our steadily increasing use of fossil fuels that exposes us to a variety of air pollutants, results in health problems and may cause death. Indoor air pollution is caused by the burning of wood and charcoal in open indoor fires. Biological hazards are threats in one organism that can translate and cause disease in another. Chemical hazards come from harmful chemicals in the air, water, soil, and may be found in our food and manufactured products. Most chemical hazards come from human sources. Cultural hazards are threats that develop within human societies, I.E.: poverty, war, motor vehicle accidents and unsafe work conditions. Lifestyle health hazards are hazards that stem from our own choices and habits. For example, smoking tobacco and not getting enough exercise. 5 most threating chemicals are, arsenic, lead, mercury, vinyl chloride (used to make certain plastics) and PCBs. 4 groups of toxic chemicals: Carcinogens- cause or promote cancer. Arsenic and vinyl chloride are examples. Mutagens cause changes or mutate DNA of our reproductive system. Sodium azide (found in most car airbag systems) and nitrous acid. Teratogens cause birth defects, ie lead and PBCs. Neurotoxins cause harm to the nervous systems of animals and humans. Examples are mercury and certain pesticides. A basic rule of toxicology is to assume that any chemical can be harmful when taken in large quantity. It is typically difficult to determine when chemicals are toxic due to many differing variables.
Problems- Multiplying infectious bacteria are becoming genetically resistant to widely used antibiotics. 1.4 million people die from tuberculosis every year. Antibiotics do not affect viruses. However, scientists have developed vaccines that prevent only a few diseases. HIV infects about 2.7 million people. There is no vaccine for it. The largest worldwide parasitic threat is malaria. According to WHO, there are about 225 million people who suffer from malaria and about 655,000 deaths resulted from it. The body’s immune system when harmed by toxins, becomes weak. Arsenic and other chemicals make the body less able to fight off pathogens. The nervous system can be harmed by long exposure to harmful chemicals. Exposure to methylmercury can cause brain damage in infants. About 60,000 children born every year are likely to have neurological problems due to being exposed to low levels of this toxin. The Endocrine system can also be affected by harmful chemicals. For example, PBCs can attach to the molecules of natural hormones and interfere with their natural functions. Phthalates are a set of chemicals being studied for possible harmful effects. Chemical manufacturers make them into polyvinyl chloride (PVC) plastic that is used to make teething rings, blood storage bags, and the plastic tubing used in hospitals. Phthalates are used as solvents in other consumer products such as hair sprays and deodorants. In some laboratory animals, high doses of phthalates have caused birth defects and malfunctioning immune systems. The European Union and 14 other countries have banned phthalates. Yet U.S. toymakers argue that they have used phthalates for over 20 years without harmful effects. The U.S. scientists have not reached an agreement on whether or not phthalates pose a threat to human health. Because of the lack of data and the high costs of regulation, about 99.5% of all chemicals used in the United States are unregulated. Poverty kills more people than flying in an airplane or chances of being by a shark. A 2010 study by British researchers and a 2007 study by the CDC discovered that about 600,000 people worldwide die from secondhand smoke. Tobacco use is the most preventable of all major environmental health threats.
What can be done? Consider that the cost of protecting a child with a basic set of vaccines is about $30 when the cost of a modest dinner for two in some of the world’s more-developed countries is $30 or less. Although infectious disease is a problem in countless less developed countries, there are simple, inexpensive ways to prevent deaths from these diseases. For example, the use of bed nets designed to keep mosquitoes off of sleeping people in tropical areas helps to reduce the number of malarial infections. Improving basic nutrition, immunizing children against major viral diseases and sharply reducing antibiotic use to promote livestock growth are a few preventive solutions that are very affordable compared to the cost of treating diseases. Because it is difficult to determine all possible health risks from exposure to chemicals. Because of this scientist argue that when there is evidence indicating that an activity can harm the environment and human health, we need to take precautionary measures to prevent this harm. This is called the Precautionary Principle. Many scientists reasonably believe that consumers should avoid using chemicals like BPA especially in products for young children, because it may act as hormone disrupter for infants. Scientists strongly call for manufacturers to find less harmful substitutes for harmful chemicals. And these scientist push for governments to require these manufacturers to take these precautionary measures. Pollution prevention is a practical way to apply the precautionary principle. For example, switching from burning coal to using renewable energy resource is easier than collecting and recycling batteries and all other products that contain mercury. Overall pollution prevention is less costly and easier than pollution cleanup. Some scientists, public officials and chemical industry representatives argue that potentially harmful new chemicals should be assumed toxic until proven safe. The European Union has enacted regulations known as Registration, Evaluation, Authorisation and Restriction of Chemical substances or REACH. In this process, the more hazardous substances are not approved for use if safer alternatives exist. Under REACH, chemical manufacturers have to show that chemicals are safe. Whereas proving a chemical is dangerous has been up to the governments, as is the case in the U.S. In 2009, experts showed that in the U.S. it is nearly impossible for the government to ban the use of hazardous chemicals. Experts have developed guidelines that everyone can use to reduce their risks in the most efficient and effective ways. Determine how much risk is acceptable. The EPA assumes that there is a 1 in 1 million chance of dying from an environmental toxin, and that is the acceptable threshold. Determining acceptable risks require some research and studying from any government agency, organization, business, or individual. Determine the actual risk involved in any decision. This is a complicated process for governments and corporations dealing with complex risks. As a result of media exaggerating the daily risks of our population, more people cannot accurately compare risks. Compare risks and carefully choose how to use resources to reduce risks. When evaluating any risks, ask yourself, “how risky is this activity, technology, and/or product, compared to other risks?” Then, the organization, business, or individual comparing them should decide how to reduce or avoid those risks. Preventing health and environmental hazards before they become costly and deadly are very important benefits from educating people about how to evaluate and reduce risks.
All photos credited to Cengage learning website. (Sky Hunt’s research is from the book)