Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants...
-
Upload
rosaline-wade -
Category
Documents
-
view
219 -
download
0
Transcript of Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants...
![Page 1: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/1.jpg)
Ch 18 Outline
18.1 Types and Effects of Water Pollution
18.2 Types and Effects of Water Pollutants
18.3 Water Quality Today
18.4 Water Pollution Control
18.5 Water Legislation
![Page 2: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/2.jpg)
Ch 18 Objectives
• Define water pollution
• Describe the types and effects of water poll.• Investigate water quality today.
• Explain water pollution control.
• Summarize water legislation.
![Page 3: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/3.jpg)
18.1 Water Pollution
• Any physical, biological, or chemical change in water quality that adversely affects living organisms or makes water unsuitable for desired uses can be considered pollution. Point Sources - discharge pollution from specific
locations- Factories, power plants, drain pipes
Non-Point Sources - scattered or diffuse, having no specific location of discharge
- Agricultural fields, feedlots
![Page 4: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/4.jpg)
18.1 Water Pollution
Non point sources continued- Atmospheric Deposition - contaminants
carried by air currents and precipitated into watersheds or directly onto surface waters as rain, snow or dry particles
![Page 5: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/5.jpg)
18.2 Types and Effects of Water Pollution
• Infectious Agents Main source of waterborne pathogens is
improperly treated human waste- Animal waste from feedlots and fields is also
important source of pathogens. At least 2.5 billion people in less developed
countries lack adequate sanitation, and about half of these lack access to clean drinking water.
![Page 6: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/6.jpg)
Infectious Agents• In developed countries, sewage treatment plants
and pollution-control devices have greatly reduced pathogens. Coliform bacteria - intestinal bacteria; used to
detect water contamination Drinking water generally disinfected via
chlorination
![Page 7: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/7.jpg)
Oxygen-Demanding Wastes
• Water with an oxygen content > 6 ppm will support desirable aquatic life. Water with < 2 ppm oxygen will support mainly
detritivores and decomposers.
• Oxygen is added to water by diffusion from wind and waves, and by photosynthesis from green plants, algae, and cyanobacteria. Oxygen is removed from water by respiration
and oxygen-consuming processes.
![Page 8: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/8.jpg)
Oxygen-Demanding Wastes
• Biochemical Oxygen Demand - amount of dissolved oxygen consumed by aquatic microorganisms. Used as a test for organic waste contamination.
• Dissolved Oxygen Content - measure of dissolved oxygen in the water
• Effects of oxygen-demanding wastes on rivers depend on volume, flow, and temperature of river water.
• Oxygen Sag - Oxygen levels decline downstream from a pollution source as decomposers metabolize waste material
![Page 9: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/9.jpg)
Oxygen Sag
![Page 10: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/10.jpg)
Sediment
• Human activities have accelerated erosion rates in many areas. Human-induced erosion and runoff contribute
about 25 billion metric tons of sediment and suspended solids to world surface waters each year.
- Obstructs shipping channels, clogs hydroelectric turbines, smothers fish eggs, blocks out light needed for photosynthesis
- Sediment can also be beneficial e.g. building coastal wetlands and nourishing floodplain fields
![Page 11: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/11.jpg)
Plant Nutrients and Cultural Eutrophication
• Oligotrophic - Bodies of water that have clear water and low biological productivity.
• Eutrophic - Bodies of water that are rich in organisms and organic material. Eutrophication - Process of increasing
nutrient levels and biological productivity.- Cultural Eutrophication - Increase in
biological productivity and ecosystem succession caused by human activities.
![Page 12: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/12.jpg)
![Page 13: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/13.jpg)
![Page 14: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/14.jpg)
• You will need to be familiar with the information found between pages 403-407.
![Page 15: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/15.jpg)
Thermal Pollution
• Raising or lowering water temperatures from normal levels can adversely affect water quality and aquatic life. Oxygen solubility in water decreases as
temperatures increase.- Species requiring high oxygen levels are
adversely affected by warming water.- Humans cause warming by discharging
heated water from power plants and other industries.
![Page 16: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/16.jpg)
Remaining Problems
• Greatest impediments to achieving national goals in water quality are sediment, nutrients, and pathogens, especially from non-point discharges. About three-quarters of water pollution in the
U.S. comes from soil erosion, air pollution fallout, and agricultural and urban runoff.
- Cattle in feedlots produce 144 million tons of manure and pet waste does not go through sewage treatment.
![Page 17: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/17.jpg)
18.3 Water Quality Today
Surface Waters in Other Countries•Sewage treatment in wealthier countries of Europe generally equals or surpasses the U.S.•In Russia, only about half of the tap water supply is safe to drink and in China 70% of surface water is unfit for consumption.•South America, Africa and Asia have poor water quality due to poverty, population growth and shift of polluting industries from countries where laws are strict to where they are lax.•Two thirds of India’s surface waters are considered dangerous to human health.
![Page 18: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/18.jpg)
Groundwater and Drinking Water
• About half the U.S. population, and 95% of rural residents, depend on underground aquifers for drinking water. For decades, groundwater was assumed
impervious to pollution and was considered the gold standard for water quality, but that is no longer true.
Methyl tertiary butyl ether (MTBE). a suspected carcinogen found in gasoline, now contaminates groundwater.
![Page 19: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/19.jpg)
Groundwater and Drinking Water
• EPA estimates 4.5 trillion liters (1.2 trillion gal) of contaminated water seep into the groundwater in the U.S. every day. Comes from septic tanks, cesspools, landfills,
waste disposal sites, etc.- 1 gal of gasoline can make 1 million gal of
water undrinkable. In agricultural areas, fertilizers and pesticides
commonly contaminate aquifers and wells. Contaminants remain for thousands of years
![Page 20: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/20.jpg)
Groundwater Pollution
![Page 21: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/21.jpg)
Groundwater and Drinking Water
• In addition to groundwater, contaminated surface waters can make drinking water unsafe. 20,000 public drinking water systems in the U.S.
have lead, pesticides, pathogens at unsafe levels.
• Estimated 1.5 million Americans fall ill from fecal contamination annually Cryptosporidium outbreaks
- Milwaukee - 400,000 sick, 100 dead
![Page 22: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/22.jpg)
Hydraulic Fracturing
• Hydraulic fracturing, or “fracking”, is a controversial technique used to extract natural gas from rock formations that are not very permeable. Examples: Shale
and coal beds.
![Page 23: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/23.jpg)
Natural Gas Deposits
• Fracturing has become an increasingly popular tool for extracting natural gas, especially with the discovery of the methane-rich Marcellus Shale.
![Page 24: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/24.jpg)
The Fracturing Process
• Fracturing fluid is pumped into a narrow hole drilled into the rock formation.
• The pressure created from this fluid causes the rock formation to crack.
• Sand is injected afterwards to fill the cracks, because it is more permeable and allows the methane to seep out. Most of the mixture injected into the rock
formation is rock and sand, however…
![Page 25: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/25.jpg)
Fracturing Fluid
• A number of hazardous chemicals are also present in the fracturing fluid. These include carcinogens and endocrine
disruptors. In a study published in 2010, the EPA
discovered contaminants in groundwater. The gas industry claims that it is
impossible for these fluids to enter groundwater.
![Page 26: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/26.jpg)
2005 Energy Policy Act
• The EPA has been unable to investigate contamination due to fracturing for two reasons:
1. The 2005 Energy Policy Act provides the industry exemption from the Clean Water and Drinking Water Acts.
2. The specific chemicals used in fracturing are protected under copyright law as trade secrets.
![Page 27: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/27.jpg)
Incidents Resulting from Fracturing
• Methane gas has entered drinking water supplies in Dimock, PA. Caused a water well explosion.
• A well explosion in Clearfield, PA sent 35,000 gallons of fracturing fluid into the surrounding forests.
• Another well in Leroy, PA experienced a leak and entered the groundwater.
![Page 28: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/28.jpg)
Impaired Waters
• Impaired waters are rivers, lakes, and estuaries that cannot fully support their aquatic biological communities.
• Top three causes: Excess sediment Nutrients (nitrogen and phosphorous) Pathogenic microorganisms
![Page 29: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/29.jpg)
Water Quality Today
Source: US EPA http://pubs.usgs.gov/fs/FS-130-01/
![Page 30: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/30.jpg)
Ocean Pollution
![Page 31: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/31.jpg)
Ocean Pollution
• In spring 2010, a beached whale died off the coast of Seattle.
• Inside the whale’s stomach was found… A pair of sweatpants A golf ball 20 plastic bags Surgeon’s gloves Duct tape Plastic pieces
• Did not play a role in whale’s death
![Page 32: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/32.jpg)
Ocean Pollution
![Page 33: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/33.jpg)
Oil Pollution
• Few coastlines in the world remain uncontaminated by oil pollution. 3 to 6 million tons of oil are released into ocean
each year, about half of which is due to marine transport.
Major oil spills from transport, military conflict, oil drilling in risky locations such as the North Sea
There are plans to drill in seismically active California and Alaskan coasts.
![Page 34: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/34.jpg)
Ocean Pollution
• Most of the oil in the ocean comes from nonpoint sources.
• The biggest one is people dumping used motor oil from their cars into the sink or storm drains. Cause more long-term buildup.
• The biggest point source is oil spills or leaks from oil platforms or tankers. The point sources are much more
concentrated and cause much more short-term damage.
![Page 35: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/35.jpg)
Water Pollution Control
• Source Reduction Cheapest and most effective way to reduce
pollution is avoid producing it or releasing it into the environment.
- Studies show as much as 90% less road salt can be used without significantly affecting safety.
- Carefully dispose of oil- Recover metals from industrial waste and
sell them
![Page 36: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/36.jpg)
Oil Spills
• Exxon Valdez (1989) – One of the worst incidents of water pollution to ever occur. High volume of oil
spilled Remote location and a
poor cleanup response Thousands of sea
birds, sea mammals, and fish were killed.
![Page 37: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/37.jpg)
Exxon Valdez and Tanker Design
• Resulted in the Oil Pollution Act of 1990 Mandated a double-hull design for oil
supertankers by 2015. Would have reduced the oil spilled by
Exxon Valdez by 60%
![Page 38: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/38.jpg)
Deep Water Horizon
• The Deepwater Horizon was a floating oil rig in the Gulf of Mexico contracted to British Petroleum.
• An explosion occurred on
this rig in April of 2010, resulting in the worst oil
spill ever.
![Page 39: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/39.jpg)
Deep Water Horizon
• The rig was working drilling and preparing a well deep in the seabed of the Gulf of Mexico when a sudden surge of oil and natural gas traveled up through the rig, causing a blowout at the surface.
![Page 40: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/40.jpg)
Deepwater Horizon
• Even as the flames were contained, the oil continued to gush out at a rate of about 60,000 barrels per day.
![Page 41: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/41.jpg)
Deepwater Horizon
![Page 42: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/42.jpg)
Aftermath
• Damage from the oil spill was the most intense in three areas: The beaches of the nearby states,
especially Louisiana, Missisippi, and Alabama.
Underwater; Oil plumes stretched as long as 10 miles in some spots.
The sea floor; Oil and residue 2-5 inches thick has been recorded in some areas.
![Page 43: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/43.jpg)
18.4 Water Pollution Control
Human Waste Disposal•More than 500 pathogenic bacteria, viruses, and parasites can travel from human or animal excrement through water.•Natural Processes
In many areas, outdoor urination and defecation is the norm.
- When population densities are low, natural processes can quickly eliminate waste, but in cities this is unworkable.
Significant proportion of dust in Mexico City is actually dried feces.
![Page 44: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/44.jpg)
Human Waste Disposal
• In many countries, especially in Asia, “night soil” (human and animal waste) is spread on fields as fertilizer, but it can cause disease.
• Until about 50 years ago, most rural areas in the U.S. depended on outhouses, which contaminated drinking water supplies.
• Development of septic fields which clean water by aeration and remove excess nutrients through bacterial action. Solids are pumped out and taken to a treatment plant.
![Page 45: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/45.jpg)
Septic Tank
![Page 46: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/46.jpg)
Municipal Sewage Treatment
• Primary Treatment - physical separation of large solids from the waste stream
• Secondary Treatment - biological degradation of dissolved organic compounds Effluent from primary treatment transferred into
trickling bed, or aeration tank- Effluent from secondary treatment is usually
disinfected (chlorinated) before release into nearby waterway.
![Page 47: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/47.jpg)
Municipal Sewage Treatment
• Tertiary Treatment - removal of plant nutrients (nitrates and phosphates) from secondary effluent Chemicals which bind or natural wetlands
• In many U.S. cities, sanitary sewers are connected to storm sewers. Heavy storms can overload the system, causing
by-pass dumping of raw sewage and toxic runoff directly into watercourses.
![Page 48: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/48.jpg)
![Page 49: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/49.jpg)
Low-Cost Waste Treatment
• Effluent Sewerage Hybrid between traditional septic tank and full
sewer system- Pump liquid tank contents to central treatment
plant rather than use drainfield
• Wetlands Effluent flows through wetlands where it is
filtered and cleaned by aquatic plants and microscopic organisms.
![Page 50: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/50.jpg)
18.5 Water Legislation
• Clean Water Act (1972) Goal was to return all U.S. surface waters to
“fishable and swimmable” conditions- For point sources, discharge permits and best
practicable control technology (BPT) are required.
Set goals of best available, economically achievable technology (BAT) for zero discharge of 126 priority toxic pollutants
![Page 51: Ch 18 Outline 18.1 Types and Effects of Water Pollution 18.2 Types and Effects of Water Pollutants 18.3 Water Quality Today 18.4 Water Pollution Control.](https://reader033.fdocuments.us/reader033/viewer/2022051416/56649e0c5503460f94af54c2/html5/thumbnails/51.jpg)
Clean Water Act (1972)
• Areas of Contention Draining or filling of wetlands is regulated
- Farmers and developers consider this the taking of private lands
Unfunded Mandates- State or local governments must spend
monies to comply with regulations but are not repaid by Congress.
Agricultural runoff is largest source of surface water degradation, but regulation remains a problem.