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Part II: Water Pollution and Treatment

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1 Part II: Water Pollution and Treatment
Unit 01 - Water Part II: Water Pollution and Treatment

2 Water Quality Definitions
Contaminant - any constituent in the water deleterious to a particular end use regardless of its origin and whether it occurs in the watershed, source or in a water supply system Pollutant - any constituent in the water source deleterious to a particular end use that is of anthropogenic origin (human activities) Pollutant = subset of contaminant Contaminants Contaminants Pollutants

3 Water Pollution Any chemical, biological and physical change in water quality that has a harmful effect on living organisms or makes it unusable for agriculture The massive quantity of pollutants produced by > 6 billion humans, their machines, plants, animals The limited supply of fresh liquid water into which most water-destined pollutants are discharged The growing number of ‘technological pollutants’ released into the environment, i.e. manufactured synthetic materials Agriculture is largest source of water pollution in the U.S. (64% of pollutants into streams and 57% of pollutants entering lakes) In general, water pollution is concerned with 3 issues, huge as they are: Remember 0.6% of the worlds total water supply? 3

4 Types of Pollution Disease-causing Agents – pathogens
Nutrients – nitrogen and phosphorus Oxygen Demanding Agents – organic waste; manure, sewage Water-soluble Inorganic Chemicals – acids, toxic metals Organic Chemicals – oil, pesticides, detergents Sediment or Suspended Material – erosion, soil Water-soluble Radioactive Isotopes – waste Heat – Industrial electric and nuclear power plants

5 Pathogens Escherichia coli Giardia sp.* Hepatitis A virus Guinea Worms
Vibrio sp.* |Cholera Escherichia coli Giardia sp.* Hepatitis A virus Guinea Worms

6 Waterborne Disease Outbreaks of waterborne diseases Milwaukee, WI
Largest outbreak of waterborne disease microorganism: cryptosporidium (in Sabino!!) Fecal Coliform Bacteria Example: E-coli Walkerton, ON E-coli outbreak (dangerous type found in cattle)

7 Nutrients Phosphorus and nitrogen are the major concerns Sources:
Human, animal (e.g., Hog Farms), and industrial waste Storm water Soil erosion Excessive use of fertilizers for crops, lawns, and home gardens

8 Nutrients High nutrient concentrations can cause Eutrophication (“well-fed” in Greek) of water bodies Eutrophication is characterized by rapid increase in plant life. An example is the algae bloom shown here. Algae blooms block sunlight so plants below die. Decomposition of dead plants consumes oxygen. Low oxygen conditions may kill fish etc. Aesthetics (color, clarity, smell) Uptake and release of toxics

9 Eutrophication in a Lake
Normal lake – low nutrients. Algae is low. Phosphorus added to streams and enters the lake. Algae growth begins. Algae at the top is so thick the algae at the bottoms dies off. Bacteria decompose this and use up available oxygen. The fish die due to lack of oxygen.

10 Oxygen Demanding Agents Pollution of Streams

11 Biological Oxygen Demand (BOD)
BOD: Oxygen is removed from water when organic matter is consumed by bacteria. Low oxygen conditions may kill fish and other organisms. Sources of organic matter Natural inputs-- bogs, swamps, leaf fall, and vegetation aligning waterways. Human inputs-- pulp and paper mills, meat-packing plants, food processing industries, and wastewater treatment plants. Nonpoint inputs-- runoff from urban areas, agricultural areas, and feedlots.

12 Fish Die

13 Oxygen Sag Curve DO BOD As pollution enters the water body, (the point of discharge) the amount of dissolved oxygen in the water steadily falls. This is because it is used up by the degrading organisms that break down the pollutants. It is also because in turbid water, larger plants are unable to obtain enough sunlight to photosynthesise efficiently, therefore decreasing oxygen production With mild pollution The oxygen levels fall slightly, but are quickly regained as the larger plants photosynthesize. In the case of heavy pollution The curve drops quite steeply to begin with, as the oxygen levels fall, due to use by the degrading organisms, but then rises steadily as the pollutants are either broken down, or dispersed by natural repair. In the case of gross pollution The oxygen levels drop to the point that no oxygen is dissolved in the water for a short period of time. After a while however, this waste is broken down enough that the photosynthesising plants receive enough light to photosynthesise, and begin releasing oxygen into the water once more.

14 Heavy Metals

15 Heavy Metals Metallic elements having a density greater than 5 g/cm3
Most are extremely toxic Water soluble Readily absorbed into plant or animal tissue Bioconcentrate Combine with biomolecules Proteins Nucleic acids Heavy Metals by Dr. Jena Hamra

16 Sources of Heavy Metals
Natural Redistributed by geologic and biologic cycles Industrial Burning of fossil fuels Environmental pollution Anti-fouling paint Heavy Metals by Dr. Jena Hamra

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18 Acid Mine Drainage Water with a high concentration of sulfuric acid that drains from mines (type?) Serious water pollution problem Damages aquatic ecosystems, pollutes bodies of water and degrades water quality

19 Acid Rain Broad term used to describe several ways that acidic precipitation falls out of the atmosphere

20 Wet and Dry Acid Rain Wet deposition refers to acidic rain, fog, and snow. Dry deposition refers to acidic gases and particles.

21 Causes of Acid Rain Sulfur dioxide (SO2) and nitrogen oxides (NOx) are the primary causes of acid rain. In the US, about 2/3 of all SO2 and 1/4 of all NOx comes from electric power generation that relies on burning fossil fuels like coal.

22 Measuring Acid Rain Acid rain is measured using a "pH" scale.
The lower a substance's pH, the more acidic it is. Pure water has a pH of 7.0. Normal rain is slightly acidic and has a pH of about 5.5. As of the year 2000, the most acidic rain falling in the US has a pH of about 4.3.

23 Buffering Capacity Acid rain primarily affects sensitive bodies of water, which are located in watersheds whose soils have a limited “buffering capacity” Lakes and streams become acidic when the water itself and its surrounding soil cannot buffer the acid rain enough to neutralize it Some lakes now have a pH value of less than 5

24 Effects on Wildlife Generally, the young of most species are more sensitive to environmental conditions than adults At pH 5, most fish eggs cannot hatch At lower pH levels, some adult fish die Some acid lakes have no fish

25 Effects on Nutrients Acidic water dissolves the nutrients and helpful minerals in the soil and then washes them away before trees and other plants can use them to grow. Acid rain also causes the release of substances that are toxic to trees and plants, such as aluminum, into the soil.

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27 Organic Chemicals

28 Biological Magnification
Concentrations increase at increasing levels in the food chain – PCBs, DDT, etc. Fig. 12–20 © Brooks/Cole Publishing Company / ITP Water Resources and Water Pollution by Paul Rich

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30 DDT DDT was a widely used pesticide that became concentrated in ocean fish DDT caused brown pelicans and ospreys to produce thin egg shells Worldwide, DDT has been banned from agricultural use but is still found in developing countries… DDT was widely used in agriculture during the 1950’s, US production banned in 1971, by that time, 4.4 billion pounds had been manufactured, banned in the states by the EPA in 1972 The danger of excessive use of DDT first became apparent in the ocean env. when it affected ocean bird populations. During the 1960’s, there was a serious decline in the brown pelican population of Anacapa Island off s. California…high concentrations of DDT in the fish eaten by the birds had caused them to produce eggs with excessively thin shells. Same thing happened to the osprey in Long Island Sound, 30

31 PCBs PCBs are industrial chemicals used as liquid coolants and insulation in industrial equipment such as power transformers PCBs enter the ocean environment through leaks and from discarded equipment PCBs can accumulate in animal tissues and affect reproduction PCB’s have been indicated as causes of spontaneous abortions in sea lions and the death of shrimp in Florida Both DDT and PCB’s (banned in 1977) generally enter the ocean through the atmosphere and river runoff. They are concentrated initially in a thin slick of organic chemicals at the ocean surface, and then they gradually sick to the bottom, attached to sinking particles….about 10 to 12 times more concentrated in coastal areas/ DDT and PCB’s are so pervasive in the ocean environment that even Antarctic ocean organisms contain measurable quantities…no agriculture or industry…wind and ocean currents bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 31

32 Oil Spills Sources: offshore wells, tankers, pipelines and storage tanks Effects: death of organisms, loss of animal insulation and buoyancy, smothering Significant economic impacts Mechanical cleanup methods: skimmers and blotters Chemical cleanup methods: coagulants and dispersing agents

33 Effects of Oil Spills Volatile Organics Compounds immediately kill many of the aquatic organisms (especially plankton and larvae) and contaminate fish Floating oil coats birds and ocean mammal; destroys natural insulation and buoyancy and causes deaths Heavy oil sinks to ocean bottom and washes into estuaries where it contaminates crabs, oysters, mussels, clams, etc. Oil slicks on beaches harm intertidal life and cause economic losses to tourism and fishing industries © Brooks/Cole Publishing Company / ITP Water Resources and Water Pollution by Paul Rich

34 Ocean Pollution: Petroleum
When oil washes up at a beach, it can negatively affect the ocean environment Oil can coat ocean organisms and render their insulating fur or feathers useless Oil on the beach from the Exxon Valdez oil spill, Alaska bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 34

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37 Exxon Valdez Oil Spill March 24, 1989, tanker in Prince William Sound, Alaska, worst oil spill in U.S. waters The most ecologically destructive oil spill in history Coated 1,600 of shoreline, killed wildlife, and caused serious contamination Exxon spent $2.2 billion on direct cleanup + $1 billion fines and damages; another $5 billion being appealed © Brooks/Cole Publishing Company / ITP Water Resources and Water Pollution by Paul Rich

38 Exxon valdez spilled almost 11
Exxon valdez spilled almost 11.6 million gallons of oil into a pristine wilderness area in crude oil from northern Alaska is carried by the pipeline down to Valdez, where it is loaded onto supertankers (can hold 53 million gallons) Ran aground on a shallowly submerged rocky outcrop, Bligh Reef. What spilled out was only 22% of her cargo, into Prince William Sound into the Gulf of Alaska, fouled over 1775 km of coastline (1100 miles) Right after the spill, Exxon spent over 2.5 billion in cleanup and $900 million in subsequent years for restoration. Molly McCammon, executive director of the Exxon Valdez Oil Spill Trustee Council, the sound will need much more time to heal. "It is clear that the oil spill affected areas have still not recovered from that earlier devastation. We know that while there is progress toward recovery, there is still oil on the beaches. We know that weathered oil can still be toxic at very low levels. We know that many resources are still not recovered and we know that the people of the region have not healed." The trustee council was established following the Alaska spill to protect habitat and monitor recovery of Prince William Sound. That means rebuilding lost populations of fish, birds, and animals. By official counts, the spill killed 250,000 seabirds, 2,800 sea otters, 300 harbor seals, 250 bald eagles and 22 killer whales. Numerous other species, from salmon to clams, also suffered casualties. More than 500 miles of remote wilderness shoreline was oiled. Yet a decade later, the river otter and the bald eagle are the only species to have recovered. Thirteen other species, such as salmon, harbor seals, and several seabirds, are listed as "recovering." Still other species, such as the sound's killer whales, have shown little sign of bouncing back, SENNER: "Killer whales have shown some small progress since the oil spill back in We've seen a gain of some three animals to the injured AB pod since However, we continue to place this species in the not recovering category because when you have an animal that lives to be 30 to 50 years old, it's simply premature to declare we've got real progress here." Sea otters--those cuddly ocean mammals that became the poster children of the oil spill--were among the hardest hit. In heavily oiled areas, sea otters have had to cope with long-term exposure to oil. Stan Senner says it may take twenty more years for these populations to fully recover. But not all the news is bad. To protect birds and animals, the trustee council spent $400 million dollars, from an out of court civil settlement with Exxon, to buy 650,000 acres of wilderness in the spill area. Molly McCammon says protecting habitat will ensure the recovery of the sound's ecosystem. McCAMMON: "These lands include 1,500 miles of shoreline, more than 300 salmon streams--incredible habitat for all of the species listed up here today." Yet to some, the most fitting conclusion to this ten-year ordeal is the end of Captain Joseph Hazelwood's legal appeals. Convicted in 1990 of illegally discharging oil he will this summer begin 1,000 hours of community service. He'll spend that time picking up trash along Alaska's highways. Two sea otters, victims of the Exxon Valdez oil spill, recuperate at a rehab facility set up in a remote cove in Kachemak Bay bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 38

39 Exxon Valdez only #53???? bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt

40 Erosion Sediment (clay, silt) is the #1 source of water pollution. Bare soil easily washes into storm drains and streams, clouding the water and suffocating aquatic life. Never leave soil exposed! Place straw over newly seeded areas. Cover your garden during winter months. Sod, seed, grow plants, or build terraces on slopes. Rock gardens can also be effective for slowing the flow of water and minimizing erosion.

41 Effects of Sediment Loading
Destruction of spawning beds Adsorption and transport of other pollutants Reduced light penetration, aquatic vegetation Greater nutrients loadings, oxygen demand Interference with navigation, flood control, recreation, industry

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44 Isotopes/Radioactive Waste
Radioactive substances are produced in the form of waste from nuclear power plants, and from the industrial, medical, and scientific use of radioactive materials.. The harmful effects of radioactive waste when ingested through drinking water include genetic mutations, miscarriages, birth defects, and certain cancers.

45 William Lawless At Savannah River, South Carolina, the US Department of Energy ran plutonium production reactors (to make plutonium for bombs) and a reprocessing plant (to separate plutonium from spent nuclear fuel) William Lawless was surprised when -- with no prior experience -- he was put in charge of radioactive waste management at the huge military complex Source: 45

46 Whistleblower Lawless wanted to do a good job, so he started asking some pointed questions: Why were liquid radioactive wastes being poured into shallow trenches, where they could leak into the soil and enter the surface waters? Why were solid plutonium-contaminated wastes being buried in cardboard boxes and covered with earth? He was told to keep quiet Instead, he went public, and promptly lost his job Source: 46

47 Post Whistle-Blowing He was hired to teach mathematics at a local college, which enabled him to make a living while he kept on talking -- to the press, on national radio and TV -- about shoddy waste management practices at Savannah River Since then, all plutonium production reactors and reprocessing plants have been shut down not only at Savannah River but throughout the US, and environmental cleanup has become a priority Source: 47

48 Heat Industrial Water Pollution
Thermal Pollution occurs when water is withdrawn, used for cooling purposes, and then heated water is returned to its original source An increase in temperature, even a few degrees, may significantly alter some aquatic ecosystems

49 Waste Heat A pollutant as dangerous to waters as more tangible of forms of waste On national scale, industrial cooling waters is a first- order source of heat Electric power generation uses 80% of cooling waters Past experience has indicated that thermal pollution has not multiplied as fast as power generation because of improvements in thermal plant efficiency and development of hydropower Nuclear plants - waste even higher proportion of heat than fossil-fuel plants

50 Types and Sources of Pollution Surface Water Pollution
Groundwater Pollution Pollution of Streams and Lakes Ocean Pollution Drinking Water Quality Waste Water Treatment Water Legislation

51 Surface Water Pollution
Occurs when too much of a harmful substance flows into a body of water. Water Pollutants are emitted from Point Sources Distinct and confined sources such as pipes from industrial or sites Controlled by onsite treatment/disposal Nonpoint Sources Diffused and intermittent Ex) runoffs from streets Associated with agriculture, mining or forestry

52 Point and Nonpoint Sources
Urban streets Suburban development Wastewater treatment plant Rural homes Cropland Factory Animal feedlot POINT SOURCES

53 Pig Farm Waste Lagoon

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55 Preventing and Reducing Surface Water Pollution
Nonpoint Sources: Reduce Runoff Buffer Zone Vegetation Reduce Soil Erosion Point Sources Clean Water Act Water Quality Act

56 Groundwater Pollution
Sources: Coal strip mine runoff Pumping well Waste lagoon Accidental spills Groundwater flow Confined aquifer Discharge Leakage from faulty casing Hazardous waste injection well Pesticides Gasoline station Buried gasoline and solvent tank Sewer Cesspool septic tank De-icing road salt Unconfined freshwater aquifer Confined freshwater aquifer Water pumping well Landfill

57 Groundwater Pollution Prevention
Monitoring Aquifers Leak detection systems Strictly regulating hazardous waste disposal Storing hazardous waste ABOVE ground

58 Groundwater Pollution Solution
Bioremediation: a method of treating groundwater pollution problems that utilizes microorganisms in the ground to consume or break down pollutants

59 Rivers Rivers have been easy targets for dumping of sewage and industrial wastes Many rivers that are in industrial areas are so polluted and low in oxygen that very few species can live in them anymore The Rhine, Danube, Illinois, Cuyahoga, and Mississippi are the worst examples of polluted rivers

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62 Pollution of Streams and Lakes
water pollution laws of 1970s greatly increased number and quality of wastewater treatment plants in U.S. also improvements in Canada, Japan, and most western European countries; large fish kills and contamination of drinking water still occur, especially in developing countries; lakes, reservoirs and ponds more vulnerable to contamination than streams because of less mixing and aeration. © Brooks/Cole Publishing Company / ITP Water Resources and Water Pollution by Paul Rich

63 Ocean Pollution

64 Ocean Pollution Coastal areas most impacted – especially wetlands and estuaries, coral reefs, and mangrove swamps Half of world's population lives within 100 km (60 miles) of oceans and 14 of 15 largest cities coastal About 35% of U.S. municipal sewage discharged virtually untreated in ocean waters Dumping of industrial waste directly into ocean off U.S. coasts stopped, but many countries still dump large quantities of toxic substances Ocean is the ultimate repository of waste - Great Pacific Garbage Patch © Brooks/Cole Publishing Company / ITP Water Resources and Water Pollution by Paul Rich

65 Pollution in Coastal Waters
Coastal waters especially are highly affected by pollution because they are: Heavily used Close to sources of pollution Shallow-water bodies Not as well circulated as the open ocean Coastal pollution is made up of ocean pollution and ocean debris bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt

66 Main Types of Ocean Pollution
Petroleum (oil) Sewage sludge DDT and PCBs Mercury Point source: clearly discernable in terms of origin (municipal sewage outfall, oil tanker spills, offshore oil well blowouts) Non-point-source pollution: ill-defined or diffused sources, runoff (harbors and marinas, TBT, powerboat pollution, invasive species, agriculture, forestry, urban runoff, ocean debris, air pollution, noise pollution, dredging bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt

67 Ocean Pollution: Sewage Sludge
Sewage sludge is the semisolid material that remains after sewage treatment Much sewage sludge was dumped offshore until laws restricted sewage dumping Sewage treated at a facility typically undergoes primary treatment, where solids are allowed to settle and water to separate, and secondary treatment, where it is exposed to bacteria-killing chlorine….sewage sludge remains It contains a toxic brew of human waste, oil, zinc, copper, lead, silver, mercury, pesticides, and other chemicals. Since the 1960’s, about 500,000 metric tons of sewage sludge were dumped into the coastal waters of southern California, more than 8 million tons in the New York Bight. Clean water act in 1972 prohibited dumping sewage into the ocean after 1981, but the cost was prohibitive, so extensions and waivers were given to many cities….remember in 1988, all the syringes and garbage that washed up on the Atlantic coast? Here’s where sewage sludge was disposed of from New York and Philadelphia…95feet deep at New York Site 58 sq miles, 130 feet deep in Philadelphia (92 sq miles)…very shallow, everything goes right to the bottom, species diversity takes a dive and some areas are completely anoxic with such a concentration of organic and inorganic matter. They moved it in 1986 to a deep water site 106 miles out to sea….fishers began noticing lower catches, and people were worried the sludge would go out into the Gulf Stream, now they dispose of sewage on land. bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 67

68 Ocean Pollution: Point Source
Are clearly discernible in terms of origin Originate from municipal and industrial facilities Bypasses and overflows from municipal sewage systems Oil tanker spills and offshore oil well blowouts Those are really what we’ve been talking about….. bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 68

69 Ocean Pollution: Non-Point Source
Non-point-source pollution comes from material washed down storm drains as “poison runoff” Includes fertilizers, pesticides, road oil, and trash Any type of pollution entering the surface water system from sources other than underwater pipelines…. Mostly, non-point source pollution in coastal and urban areas arrive at the ocean directly from storm drains. Because non-point source pollution comes from so many locations and sources, its difficult to pinpoint where it originates, though the cause may be readily apparent, like trash that is washed down a storm drain… Pesticides and fertilizers from agriculture, oil from cars when it rains. The amount of road oil and improperly disposed oil regularly discharged each year into US waters is as much as 26 times the amount of the Exxon Valdez oil spill! bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 69

70 Plastic in the Ocean Environment
Either does not biodegrade or not in human time… Floats Has high strength Is ingested by and entangles ocean animals However, plastic floats, and is not biodegradable, and strangles ocean organisms and birds that have been caught in plastic netting and packing straps….ocean turtles have been killed when they ingested plastic bags, mistaking them for plankton or jellyfish…so it is illegal to dump plastic anywhere in the ocean.. Female northern elephant seal bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 70

71 Ocean Dead Zones

72 Wastewater Treatment Objectives
Wastewater treatment systems take human and industrial liquid wastes and make them safe enough (from the public health perspective) to return to the aquatic or terrestrial environment. In some cases, wastewater can be clean enough for reuse for particular purposes. Wastewater treatment systems use the same processes of purification that would occur in a natural aquatic system only they do it faster and in a controlled situation. isis.csuhayward.edu/alss/Geography/ mlee/geog4350/4350c4f01.ppt

73 Sewage or Wastewater Treatment
Sewage or wastewater is composed of sewage or wastewater from: Domestic used water and toilet wastes Industrial effluent (Toxic industrial water is pretreated) Livestock wastes ** microbes degrade organic compounds ** elimination of pathogens occurs

74 Wastewater Treatment Types of treatment systems include:
Septic Tanks or Wastewater Treatment Plants (WWTPs). Septic Tanks typically treat small volumes of waste (e.g., from a single household, small commercial/industral) WWTPs typically treat larger volumes of municipal or industrial waste.

75 Septic Tanks Approx. 22 million systems in operation ( 30% of US population) Suitability determined by soil type, depth to water table, depth to bedrock and topography Commonly fail due to poor soil drainage Potential contaminants: bacteria, heavy metals, nutrients, synthetic organic chemicals (e.g. benzene)

76 Sewage Treatment 1. Primary Treatment (Physical Process)
Wastewater or sewage treatment is a multistep process: 1. Primary Treatment (Physical Process) Removal of large objects using grates and screens Settling to remove suspended solids (primary sludge)

77 Sewage Treatment Secondary Treatment (Microbial Process)
Supernatant or primary effluent contains high levels of dissolved organic load (Biological Oxygen Demand) Aeration to stimulate aerobic degradation activated sludge reactor trickling filter reactor bacteria degrade organic carbon to CO2

78 Anaerobic Digestion of Sludge
Sludges from the primary and secondary treatment settling tanks are pumped into an anaerobic digester Sludges contain cellulose, proteins, lipid and other insoluble polymers Anaerobic bacteria digest the sludge to methane and carbon dioxide

79 Sewage Treatment Pathogen Removal by Activated Sludge
More than 90% of E.coli. and Salmonella are destroyed Bacteria are removed by inactivation, grazing by ciliated protozoa, and adsorption to sludge solids Viruses are removed mainly by adsorption process

80 Sewage Treatment Tertiary Treatment (Physicochemical Process)
Precipitation Filtration Chlorination Treated water is discharged to waterways Used for irrigation Recycled into drinking water expensive process, sharply reduces inorganic nutrients (PO4, NO3)

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82 Water Reuse Inadvertent: Indirect: Direct:
water is withdrawn, treated and returned to the environment Indirect: Ex) the wastewater renovation and conservation cycle Direct: The use of treated wastewater that is piped directly from a treatment plant to the next user

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84 Reusing Wastewater Currently, treated wastewater, no matter how “clean” cannot be directly mixed with treated raw water and supplied as potable (from Latin potare = “to drink”) water (most places) However, if a dual plumbing system is available, wastewater can be piped into facilities for specific, approved uses for which non- potable water is adequate (process water, irrigation, sanitary use, etc.) Dual plumbing systems in America are colored purple to distinguish pipes, valves, taps, etc. from potable ones (e.g. Las Positas CC and the adjacent industrial park has this) Arizona has ambitious water reuse plans calling for 19 percent of all water needs to be met through reclaimed wastewater. Los Angeles has set the goal of reusing 40 percent of its municipal wastewaters within 20 years. St. Petersburg, Florida, completely reuses all of its wastewater and discharges none to its surrounding lakes and rivers. The city has developed dual water distribution systems—one for delivering drinking-quality water and one for delivering treated wastewater. The treated water costs about one-third less than the drinking-quality water. isis.csuhayward.edu/alss/Geography/ mlee/geog4350/4350c4f01.ppt

85 Indirect Use of Wastewater
Increasingly, treated wastewater is being used in Aquifer Recovery and Storage projects, used to recharge and protect groundwater that will ultimately be used for potable supplies. In Israel and the Netherlands, treated wastewater is allowed to percolate into and filter through deep sand dunes or permeable sandstone rocks to deep aquifers and is pumped out below and sent to raw water treatment plants. In California, many plans exist for recharging groundwater basins with wastewater as long as the groundwater has adequate residence times. isis.csuhayward.edu/alss/Geography/ mlee/geog4350/4350c4f01.ppt

86 Wastewater Renovation and Conservation Cycle
Steps: 1. Return of treated wastewater to crops 2. Renovation or natural purification by slow percolation of the wastewater into soil to eventually recharge the groundwater resource with clean water 3. Reuse of the treated water

87 Water Pollution and Environmental Law
The branch of law dealing with conservation and use of natural resources and control of pollution

88 Water Quality Standards
In most countries, water quality standards have gradually emerged and are still evolving for different water uses Standards are a function of our ability to detect and remove contaminants our understanding and/or fear of their actual or possible impacts isis.csuhayward.edu/alss/Geography/ mlee/geog4350/4350c4f01.ppt

89 U.S. Water Quality Standards
The EPA have recorded at least 700 contaminants that have been found in municipal drinking water supplies around the country, many of which are harmful to humans The EPA currently requires the monitoring and reporting of some 83 variables and have set maximum contaminant levels for each (MCLS). This will likely increase soon isis.csuhayward.edu/alss/Geography/ mlee/geog4350/4350c4f01.ppt

90 Legal Attempts to Control Water Pollution
Clean Water Act 1977, now a state-federal partnership The Porter-Cologne Water Quality Control Act 1987 Federal Water Pollution Control Act 1972 amended to create: Safe Drinking Water Act, 1974, amended 1996 London Dumping Convention (1975) is the international treaty regulating disposal of wastes generated by normal operation of vessels MARPOL 73/78 is implemented in the U.S. by the Act to Prevent Pollution from Ships, under the lead of the U.S. Coast Guard The Water Quality Act (State of California) :Under the Porter-Cologne Water Quality Control Act (Porter-Cologne), the State Water Resources Control Board (State Board) has the ultimate authority over State water rights and water quality policy. Porter-Cologne also establishes nine Regional Water Quality Control Boards (Regional Boards) to oversee water quality on a day-to-day basis at the local/regional level. Regional Boards engage in a number of water quality functions in their respective regions. One of the most important is preparing and periodically updating Basin Plans,(water quality control plans). Each Basin Plan establishes: 1) beneficial uses of water designated for each water body to be protected; 2) water quality standards, known as water quality objectives, for both surface water and groundwater; and 3) actions necessary to maintain these standards in order to control non-point and point sources of pollution to the State's waters. The Federal Act established the basic structure for regulating discharges of pollutants into the waters of the United States. It gave EPA the authority to implement pollution control programs such as setting wastewater standards for industry. The Clean Water Act also continued requirements to set water quality standards for all contaminants in surface waters. The Act made it unlawful for any person to discharge any pollutant from a point source into navigable waters, unless a permit was obtained under its provisions. It also funded the construction of sewage treatment plants under the construction grants program and recognized the need for planning to address the critical problems posed by nonpoint source pollution. Safe drinking water act aims to ensure that drinking water is safe from the source to the tap: sets national standards for drinking water, sets enforceable maximum contaminant levels. This convention was established to control pollution of the sea by dumping of wastes which could create hazards to human health or to harm living resources and ocean life, to damage amenities, and to interfere with other legitimate uses of the sea. It also encourages regional agreements supplementary to the Convention.It contains three Annexes: dumping of matter listed in Annex I is prohibited; dumping of matter listed in Annex II is allowable only by special permit; dumping of matter listed in annex III is allowable only by general permit. It calls on Parties "to promote measures to prevent pollution by hydrocarbons, other matter transported other than for dumping, wastes generated during operation of ships etc., radioactive pollutants and matter originating from exploration of the sea bed."The Convention was adopted on 29 December 1972 in London, Mexico City, Moscow and Washington, D.C., and entered into force on 30 August 1975 161 countries are parties as of December regulates carrying of oil, noxious liquids in the hold of ships, hazardous substances, sewage, and garbage from ships, air emissions from ships. bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt 90

91 Clean Water Act The Clean Water Act is a 1977 amendment to the Federal Water Pollution Control Act of 1972 Set the basic structure for regulating discharges of pollutants in the US The law gave EPA the authority to set water quality standards for industry and for all contaminants in surface waters The CWA makes it unlawful for any person to discharge any pollutant from a point source into navigable waters unless a permit (NPDES) is obtained The amounts and types of pollutants than can be discharged or allowed to run in to waters from watersheds are regulated Environmental Science ENSC Pollution in the Bay-Delta

92 Safe Drinking Water Act
The Safe Drinking Water Act (1974) was established to protect the quality of drinking water in the U.S This law focuses on all waters actually or potentially designed for drinking use, whether from above ground or underground sources Environmental Science ENSC Pollution in the Bay-Delta

93 Current Law Regulating Ocean Dumping
The only substance that is illegal to dump anywhere in the ocean is plastic bss.sfsu.edu/ehines/geog600/ Freshwater%20and%20ocean%20Pollution.ppt

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