Water pollution is defined as the presence of unwanted substances beyond the levels considered acceptable for health or aesthetics. These substances may include organic matter, heavy metals, minerals, sediment, biological contaminants, and toxic chemicals.
Humans are solely responsible for the increasing presence of water contamination. All problems can fall under nine basic categories where humans are directly responsible.
- Mining This industry releases heavy metals – mercury, cadmium, and lead as well as such radioactive material as uranium. All this leads to acidity and erosion. Radon also poses a greater health risk than any other environmental pollutant and, according to the EPA, may be responsible for more cancer deaths than all other drinking water contaminants combined. The natural decomposition of uranium produces the radioactive gas, radon.
- Drilling for oil and natural gas Texas alone has reported at least 23,000 cases of groundwater and surface contamination linked to petroleum exploration. Since most of the drilling is done in remote areas, the impact does not receive as much public attention. Waste dumping is not totally regulated and rarely enforced.
- Agriculture and forestry Pesticides leech into the water through the ground. Factory farms produce the majority of the pollution because of the large amounts of animal wastes. Deforestation causes runoffs and erosion. Wetlands become choked with silt, thus destroying many eco-systems.
- City drainage systems Lawn fertilizers and toxic chemical runoffs from streets are the major sources. Rain also pushes such things as oil, soot, metals, animal wastes, dirt, and litter into the water system. Residents dump their motor oil, toxic paint substances, and medications into the sewer system as well.
- Landfills The EPA estimates that there may be as many as 75,000 industrial landfills and 15,000 municipal landfills just in the United States. American industry generates over 80 million pounds of hazardous waste every year, with a large percentage dumped into landfills. Only a small percentage is disposed of in a way that is considered environmentally secure. Between 1950 and 1975, the top 14% of the nation’s chemical companies that owned and operated 1600 facilities, dumped 1.5 trillion pounds of industrial waste at over 3,600 sites. Rain falling on these sites leeched contents into the groundwater. Long after the end of the landfill, the leeching is still taking place.
- Water and sewage treatment plants Runoff during heavy rains occasionally causes a plant to bypass the treatment, mixing sewage with water which flows on into waterways. Another problem is ships. Waste dumping from ships into harbors and bays are creating a hazard that is now finally being recognized.
- Domestic septic yanks and cesspools The EPA estimates that 29% of the American population, including an estimated 20 million single-family households, relies on this form of sewage disposal. Excessive concentrations of nitrates, phosphates, viruses, and microorganisms, as well as automotive oil, antifreeze, batteries, medications, paint and paint removers, solvents, lawn and garden products – especially pesticides – reach the water through septic systems and cesspools. In Hawaii, this is done through dumping into underground lava tubes, resulting in poisonings from eating reef fish – not to mention what it does to the ecosystem of the reef.
- Underground gasoline storage tanks There are an estimated hundreds of thousands of such tanks that were installed across America during the 1950’s. Most of them are made of steel, including the piping, and were designed to last only about twenty years. Corrosion causes them to leak. Gasoline contamination to an aquifer may render it useless for decades. Civilization is polluting water at a much faster rate than nature’s ability to cope.
- Synthetic chemicals These pose a threat. Many of these cannot be broken down by subsurface microorganisms. Such chlorinated hydrocarbons as pesticides, aldrin / dieldrin, chlordane / heptachlor, kepone, mirex, trichloroethylene (TCE), tetrachloroethylene / perchloroethylene (PCE), and carbon tetrachloride are especially difficult. Huge volumes of these chemicals are produced, used, and disposed of every year.
The United States alone uses about 350 billion gallons of fresh water about 1,400 gallons per person every day. That is more than any other industrialized country and many more times than any developing country.
- 41% is used for irrigated agriculture most of which goes to animal feed
- 38% is used to cool electric power generating plants
- 11% by industry
- 10% by the public in tap water
The EPA has catalogued over 250,000 serious unsafe water violations affecting over 120 million people on public water systems, while those on private wells fare even worse.
There are at least 700 pollutants found in the drinking water, but the EPA is required to set standards for only about sixty of them, and these standards are routinely violated without consequence. Out of the 250,000 violations, the states took just over 2,600 enforcement actions, while the EPA took about 600.
Municipalities struggle with outdated technology. Over 70,000 different chemical compounds are now in use by industry, agriculture, and private citizens, with 5,000 new and unproven chemical compounds being added into the environment each year. That amounts to 18 billion pounds of new pollutants every year.
Governments are finally being forced to admit that outdated water treatment facilities are incapable of coping with the flood of environmental toxins that are permeating water supplies. Drinking tap water is now becoming a national public health risk with one in six people drinking lead-contaminated water.
One in three cases of gastrointestinal illness is being attributed to tap water microorganisms. The old slogan, “Think before you drink,” may not be limited to alcohol.
The National Centers for Disease Control and Prevention confirm that nearly 1,000,000 people are sickened, 350,000 are exposed to dangerous levels of carcinogens other than chlorine, and approximately 900 die each year from drinking contaminated water. Canada is not exempt, with recent media attention on Walkerton, Ontario. Many other communities issue boil water advisories, yet this does not begin to keep pace with the problem.
A single class of drinking water contaminant, known astrihalomethanes and their chemical cousins, is responsible for approximately 11,000 cases of bladder and rectal cancers each year. This is twice the number that die from fires and more than are killed by handguns.
Chlorinated water can now be directly linked to heart disease and cancer, especially bladder cancer.
Lead causes water to taste sweet, causing people to think that there is nothing wrong with it. Over 90% of American households still have lead in their water from water pipes – that have soldered connections – leading into the house. Lead can also be found in the brass alloys of the faucets and from submersible pumps.
: National Geographic (Nov. 1993) stated that
“Water can carry some of our most serious diseases typhoid, dysentery, hepatitis yet still look clear in the glass.”
Bottled water may yet become part of the everyday household just as television and the telephone are, as it is in many countries of the world already. But, can we even rely on bottled water?
By law, bottled water does not have to be any cleaner than ordinary tap water and, depending on the region, anywhere from 25-75% of the bottled water is nothing but regular tap water bottled in one city and shipped to another.
Non-chlorinated water provides a perfect setting for the growth of pathogenic bacteria, which can double in a 20-minute period in the oxygen-free atmosphere provided by the bottling process. The EPA performed a random study of producers of bottled water and found serious sanitation deficiencies at ALL plants chosen.
Here is what they found:
- Plastic bottles shipped without lids which arrived at their destination and were stored open until caps were manually placed on the bottles and sold.
- Employees were not required to avoid the bottling area if they had cuts, a cold, or other infections.
- A one-in-ten sampling of bottled water showed large numbers of pathogenic bacteria after 63 days of storage in EVERY sample.
- Further tests revealed that the labelling did not match the contents. Analysis of one or more revealed significant amounts of chlorine, sulfate, nitrates, copper, manganese, lead, iron, zinc, mercury, and arsenic.
Activated carbon is often mistakenly called charcoal. The two are quite different. Activated carbon is a charcoal-like substance made from coal, wood, or petroleum products specially treated with steam and high heat in the absence of oxygen. Contaminants are not absorbed by the carbon, but cling to its surface. It can remove volatile organic chemicals (some pesticides and chemicals) and most halogenated organic compounds like PCB’s and PBB’s; chlorine, but not compounds created by chlorine (trihalomethanes like chloroform); and some heavy metals. It will NOT remove most biological contaminants asbestos particles, fluorides, nitrates or other salts, or many inorganic chemicals.
Technology has improved activated carbon with a new product referred to as catalytic or absorptive carbons. The biggest drawback to this type of filter is that the water can still contain the bacteria they trap.
Water Treatment Systems
Public water treatment systems basically use the following steps to purify their water supply:
- Coagulation – Chemicals are added to create small jelly-like particles called floc, which collect dirt and other solids suspended in the water.
- Flocculation – Water is gently mixed so floc particles clump together.
- Settling Larger floc particles and sediment are slowed so they can fall to the bottom, creating sludge.
- Filtration – Water is passed through a granular medium, as sand or crushed hard coal.
- Disinfection Chlorine or other chemicals are added to the water to kill potential disease-causing bacteria and organisms.
- Corrosion control Chemical-like quicklime is added to reduce the water’s acidity to prevent corrosion in water, pipes, and the consequent leeching of dangerous metals into the water supply.
- Fluoridation Fluroide is added, supposedly to prevent tooth decay. It is now known to cause more harm than good.
- Aeration Air passes through water so volatile organic compounds will evaporate and be removed.
Municipal water should be tested for:
Private wells or water systems should also test for:
- biological contamination
- herbacides and pesticides, especially if living in the vacinity of landfills (radon, toxic waste), mines (mercury, cadmium, and arsenic), underground storage tanks (fuels and oils)
- nitrate levels, which can fluccuate widely according to the season.
Such microbes as Cryptosporidium and Giardia are not affected by chlorine. Many other contaminants are not subject to regulatory testing.
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This page was updated in November 2005.