Thursday, September 13, 2007

Water pollution in the Great Lakes



Post By Voon Chen Li

1. Introduction
2. Why so polluted?
3. Effects of water pollution
4 Dilution is NOT the solution!
5. Lake Erie: "We have met the enemy and he is us".
6. Further resources and references



1 Introduction
The pollution of our waterways became a national issue in June of 1969, the day that the Cuyahoga River, flowing through Cleveland, Ohio, on its way to Lake Erie, caught on fire because it was so polluted. Although this was not the first time that the Cuyahoga River had been in flames, the 1969 fire caught the attention of the nation and the fight began for increased water pollution controls, which eventually led to the Great Lakes Water Quality Act and Clean Water Act in the 1970s.
Water pollution is defined as a change in the chemical, physical and biological health of a waterway due to human activity. Ways that humans have affected the quality of the Great Lakes water over the centuries include sewage disposal, toxic contamination through heavy metals and pesticides, overdevelopment of the water's edge, runoff from agriculture and urbanization, and air pollution.



2 Why so polluted?
Under the belief that water could dilute any substance, industries and individuals during the 18th and 19th centuries often used rivers and lakes as garbage cans. Industrial effluent, raw sewage and animal carcasses would often be dumped into waterways, without much thought of contamination and downstream neighbors.
This practice started changing in the 20th century as people became aware of the importance of clean water to health. However, as more industries and people moved into the Great Lakes region, the more the rivers and lakes became polluted. Today, pollutants enter the Great Lakes in many different ways, but the main three entryways of pollutants are point source, nonpoint source and atmospheric pollution.
Point source pollutionWhen pollutants enter the waterway though a specific entry point, such as a drainpipe draining directly into a river, it's called point source pollution. Industrial water discharges and sewage treatment plants are the main culprits of this type of pollution. Point source pollutants can include many different organic and inorganic substances, including human waste and toxic metals.
Point source pollution can be traced to a specific discharge point and owner; therefore, it has been the easiest source of pollution to control and regulate. Since the Clean Water Act of 1972, nearly 100 percent of all industrial plants use control measures to reduce their toxic discharge, and the number of sewage treatment facilities has doubled.
Nonpoint source pollutionIn contrast to point source pollution, nonpoint source (or NPS) pollution comes from many different diffuse sources and is extremely difficult to regulate and control; therefore, many experts believe that NPS pollution is the top hazard facing the Great Lakes today.
NPS pollution is mainly caused by runoff, when rain and snowmelt move over the land, picking up pollutants along the way and eventually dumping the pollutants into rivers and lakes. Some common NPS pollutants include fertilizers and pesticides from agricultural lands and homeowners; oil, grease and salt from highways; sediment from construction sites and eroding shorelines; and animal and human waste.
Atmospheric pollutionAtmospheric pollution (or air deposition) is another form of nonpoint source pollution, though instead of polluting via runoff, the pollution falls from the sky. As water moves through the hydrologic cycle, it falls as rain or snow and then evaporates into the air from land and surface water. Pollutants emitted into the air, such as through smoke stacks, follow this same path, and can be carried through the atmosphere and deposited into waterways hundreds of miles away from its source. Acid rain is the most well-known form of atmospheric pollution.
The major sources of atmospheric pollution include coal-burning energy plants and waste incinerators. The combustion of fossil fuels and waste (such as from hospitals) produces large amounts of mercury in the air, a toxic chemical that is fatal to humans and animals in large quantities. Phosphorus and polychlorinated biphenyls (PCBs) are also transported to waterways via air deposition.


3 Effects of water pollution
Water pollution affects the health of the waterway, the health of the organisms living in and around the waterway, and, eventually, the health of humans. The effects of water pollution can range from aquatic deformities to contaminated fish to "dead" lakes.
Aquatic diseases and deformitiesAs virtual "canaries in a gold mine," the deteriorating health of fish and wildlife speaks volumes about the need to clean up the Great Lakes. Heavy metals such as mercury and lead, and human-made organic chemicals such as pesticides, biomagnify as they move up the food chain, resulting in tumors and death for predatory animals, such as lake trout, herring gulls, and even humans.
Toxic pollutants can also alter the genetic makeup of an organism, resulting in either death or extreme deformities. Studies have found cormorants suffering from cross-billed syndrome at rates 42 percent times the natural occurence, while terns exhibit birth defects from dioxin, PCBs and furan exposure at 31 times the normal levels. Other examples of deformities include large fish tumors and three-legged frogs.
Human health issuesPersistant Organic Pollutants, or POPs, such as dioxin, PCBs and DDT, are chemical substances that persist in the environment and bioaccumulate through the food web; therefore, POPs can also cause sickness and disease in humans, who are at the end of the food chain. People who regularly consume a lot of fish will have larger levels of toxic chemicals in their bodies than those who only eat fish occasionally. While scientists are still studying the effects of high chemical levels in humans, studies have suggested that toxic chemicals can lead to reproductive problems, cancer and neurological disorders.
People who are most at risk of health problems due to contaminated fish consumption are those with weakened immune systems, including children, pregnant women and the elderly. Those in the "high-risk" category should either abstain from eating Great Lakes fish, or only eat one meal consisting of fish every week or month, depending on the type of fish. Each state/province in the Great Lakes region publishes a yearly fish advisory; of the 1,400 fish consumption advisories in the United States, more than 1,000 are found in the eight Great Lakes states. See GLIN's fish advisory page for more information.
Other human health issues related to water pollution include drinking water contamination and skin infection, caused by bacterial contamination.
EutrophicationBefore Europeans arrived in the Great Lakes region, the Great Lakes were mainly oligotrophic lakes, meaning they contained little plant nutrients and were continuously cool and clear due to their immense size and depth. Oligotrophic lakes can support high levels of animal life and receive proper amounts of nutrients, mainly phosphorous and nitrogen, from natural sources, such as decomposing plant matter.
European settlement and industrialization changed all of that. The amount of nutrients entering the Great Lakes has intensified greatly, mainly due to increased urbanization and agriculture, leading to increased biological growth, or eutrophication. Under eutrophic conditions, nutrient loading (more nutrients than the waterbody can handle) stimulates excessive plant growth, which in turn decreases the amount of oxygen in the water and eventually kills off certain species of animal life. Other pollution-tolerant species, such as worms and carp, grow more rapidly; thus, the ecological balance of the lake is significantly altered.

4 Dilution is NOT the solution!
At one time, many people believed that water was capable of diluting toxic substances to the point of rendering them harmless. However, we have since learned that this is not the case, especially in regards to POPs, which persist in bodies of water -- no matter how diluted they are -- and accumulate in the food chain. The United States and Canada realized that the health of the Great Lakes could be best achieved through cooperation, and since the 1970s both countries have been working toward a cleaner Great Lakes system.
Water quality legislationThe International Joint Commission (IJC), created as a result of the Boundary Waters Treaty of 1909, conducted studies on the water quality of the Great Lakes in the 1960s, determining that excessive phosphorus was causing eutrophication in the Great Lakes, particularly in lakes Ontario and Erie.
In response to the IJC study, the United States and Canada signed the Great Lakes Water Quality Agreement (GLWQA) in 1972. GLWQA established pollution control levels (mainly to reduce phosphorus levels in lakes Ontario and Erie), binational water quality research and monitoring efforts.
In 1978, the Agreement was renewed to reduce the phosphorus levels for all of the Great Lakes and called for the elimination of all POPs discharging into the lakes. This amended agreement focused on the Great Lakes as a connected system and established an objective to restore and maintain "the chemical, physical and biological integrity of the Great Lakes basin ecosystem."
The United States and Canada most recently renewed the GLWQA in 1987, this time focusing on NPS pollution, contaminated sediments and airborne pollutants. New management approaches also were established, including Remedial Action Plans (RAPs) and Lakewide Management Plans (LaMPs). RAPs focus on the 43 (now 42) geographic Areas of Concern, and LaMPs are designed to improve the environmental quality of the open waters of each of the Great Lakes, with a particular focus on critical pollutants.
The IJC publishes biennial reports on how well the United States and Canada are following the regulations and goals established in the GLWQA. The most recent report in 2000, while acknowledging that the two countries have done much to control point source pollution of toxic chemicals, criticized both countries for their failure to control the rise of contaminated sediments and airborne pollutants, which are both caused by toxic chemicals and lead to many wildlife and human health problems.
Other legislation and government organizations impacting the water quality of the Great Lakes include the following:
United States
· Clean Water Act of 1972 and 1977
· National Environmental Protection Act (1969)
· Great Lakes Toxic Substances Control Agreement (1986)
· U.S. Environmental Protection Agency (EPA)
· EPA-Great Lakes National Program Office (GLNPO)
· State EPA or environment management offices: IL IN MI MN NY OH PA WI
· Great Lakes Commission
· Great Lakes Environmental Research Laboratory
· Great Lakes Fishery Commission
Canada
· Canada Water Act
· Canadian Environmental Protection Act of 1988
· Environment Canada
· Ontario Ministry of the Environment
Grassroots, community and individual involvementWhile legislation and laws ultimately determine the regulation of pollution entering the lakes, advocacy efforts are what often prompt governments to enact and enforce these laws. Major Great Lakes advocacy groups are listed below.
Individuals can also do their part in reducing water pollution. Examples include the following: stop using lawn pesticides and fertilizers; dispose of oil and paint in a recycle center; control soil erosion by replacing sections of your lawn (or your entire lawn!) with native plants; and keep litter and leaves out of your street gutters and storm drains.
Great Lakes UnitedLake Michigan FederationNational Wildlife Federation Great Lakes Field OfficeSierra Club Eastern Canada ChapterSierra Club Midwest Field Office and state chapters


5 Lake Erie: "We have met the enemy and he is us"*
In the 1960s, Lake Erie was declared "dead," though, ironically, it was full of life -- just not the right kind. Eutrophication had claimed Lake Erie and excessive algae became the dominant plant species, covering beaches in slimy moss and killing off native aquatic species by soaking up all of the oxygen. The demise of Lake Erie even made it into a Dr. Seuss book, The Lorax.
Lake Erie is the shallowest and warmest of the five Great Lakes, and the basin is also intensively developed with agriculture, urban areas, industries and sewage treatment plants. For decades, pollution filled Lake Erie with far more nutrients than the lake could handle, with phosphorous being the main culprit. Phosphorous is a fertilizer that induces plant growth and algae and was also found in many commercial detergents at the time. Plants began growing, dying and decomposing in Lake Erie, creating anoxia (severe deficiency of oxygen) at the bottom of the lake and leaving the water's surface putrid and mossy. The lack of oxygen killed fish and other aquatic species, and the smelly surface repelled anglers, tourists and those living around Lake Erie. Heavy metals also had contaminated much of the fish population of Lake Erie.
In response to public concern and recommendations by the International Joint Commission, the Great Lakes Water Quality Agreement was signed by the United States and Canada in 1972. The Agreement emphasized the reduction of phosphorous entering lakes Erie and Ontario, and in 1977 maximum levels for phosphorous were added to the Agreement. Also, phosphorus in detergents was finally banned. Coupled with the U.S. and Canadian Clean Water acts, the GLQWA did much to reduce the phosphorus levels in Lake Erie.
Today, phosphorus loads in Lake Erie are now below the maximum allowed in the GLWQA, and eutrophication has been controlled. Algae and excessive plant growth has been reduced, and native plants are once again growing in sections of the lake. Lake Erie still has many problems -- such as non-native invasive species, contaminated sediments and closure of beaches due to sewage contamination. But, through international cooperation and public advocacy, the lake is no longer considered "dead," and, hopefully, people have a better understanding and concern for the effects of human activity on water quality in the Great Lakes and beyond.


6 More to come ...
Although phosphorus levels in lakes Ontario and Erie have decreased by almost 80 percent since the 1970s and many regulations have been placed on toxic chemical dumping, water pollution in the Great Lakes is still causing severe damage to aquatic ecology and to our own health and quality of life. Beaches are consistently closed due to bacterial contamination, drinking water contamination has caused sickness and deaths around the region, many of our fish are poisoned with chemicals, and the sediments at the bottom of the lakes are becoming increasingly toxic. ... and then the silver liningBut the Great Lakes and waterways are showing signs of improvement. In late May 2001, the Cleveland Plain Dealer reported the Cuyahoga River in Ohio -- the river that caught on fire in 1969 -- is now showing healthier fish than it has in decades. Researchers attribute the success to the cleanup of industries that had originally sent their wastes into the river, as well as better maintenance of sewer systems and sewage treatment plants in the Cuyahoga watershed.

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